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Sample records for adsorbed brp batch

  1. Technique of ethanol food grade production with batch distillation and dehydration using starch-based adsorbent

    NASA Astrophysics Data System (ADS)

    Widjaja, Tri; Altway, Ali; Ni'mah, Hikmatun; Tedji, Namira; Rofiqah, Umi

    2015-12-01

    Development and innovation of ethanol food grade production are becoming the reasearch priority to increase economy growth. Moreover, the government of Indonesia has established regulation for increasing the renewable energy as primary energy. Sorghum is cerealia plant that contains 11-16% sugar that is optimum for fermentation process, it is potential to be cultivated, especially at barren area in Indonesia. The purpose of this experiment is to learn about the effect of microorganisms in fermentation process. Fermentation process was carried out batchwise in bioreactor and used 150g/L initial sugar concentration. Microorganisms used in this experiment are Zymomonas mobilis mutation (A3), Saccharomyces cerevisiae and mixed of Pichia stipitis. The yield of ethanol can be obtained from this experiment. For ethanol purification result, distillation process from fermentation process has been done to search the best operation condition for efficiency energy consumption. The experiment for purification was divided into two parts, which are distillation with structured packing steel wool and adsorption (dehydration) sequencely. In distillation part, parameters evaluation (HETP and pressure drop) of distillation column that can be used for scale up are needed. The experiment was operated at pressure of 1 atm. The distillation stage was carried out at 85 °C and reflux ratio of 0.92 with variety porosities of 20%, 40%, and 60%. Then the adsorption process was done at 120°C and two types of adsorbent, which are starch - based adsorbent with ingredient of cassava and molecular sieve 3A, were used. The adsorption process was then continued to purify the ethanol from impurities by using activated carbon. This research shows that the batch fermentation process with Zymomonas mobilis A3 obtain higher % yield of ethanol of 40,92%. In addition to that, for purification process, the best operation condition is by using 40% of porosity of stuctured packing steel wool in distillation

  2. A versatile noninvasive method for adsorber quantification in batch and column chromatography based on the ionic capacity.

    PubMed

    Huuk, Thiemo C; Briskot, Till; Hahn, Tobias; Hubbuch, Jürgen

    2016-05-01

    Within the Quality by Design (QbD) framework proposed by the International Conference on Harmonisation (ICH), high-throughput process development (HTPD) and mechanistic modeling are of outstanding importance for future biopharmaceutical chromatography process development. In order to compare the data derived from different column scales or batch chromatographies, the amount of adsorber has to be quantified with the same noninvasive method. Similarly, an important requirement for the implementation of mechanistic modeling is the reliable determination of column characteristics such as the ionic capacity Λ for ion-exchange chromatography with the same method at all scales and formats. We developed a method to determine the ionic capacity in column and batch chromatography, based on the adsorption/desorption of the natural, uv-detectable amino acid histidine. In column chromatography, this method produces results comparable to those of classical acid-base titration. In contrast to acid-base titration, this method can be adapted to robotic batch chromatographic experiments. We are able to convert the adsorber volumes in batch chromatography to the equivalent volume of a compressed column. In a case study, we demonstrate that this method increases the quality of SMA parameters fitted to batch adsorption isotherms, and the capability to predict column breakthrough experiments. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:666-677, 2016. PMID:27324662

  3. Single stage batch adsorber design for efficient Eosin yellow removal by polyaniline coated ligno-cellulose.

    PubMed

    Debnath, Sushanta; Ballav, Niladri; Maity, Arjun; Pillay, Kriveshini

    2015-01-01

    Polyaniline-coated lignin-based adsorbent (PLC) was synthesized and used for uptake of reactive dye eosin yellow (EY) from aqueous solution. The adsorption capability of the adsorbent was found to be more effective than the unmodified adsorbent (LC). In particular, the adsorption capability of the PLC was effective over a wider pH range. This could be owing to its higher point of zero charge, which is more favorable for the uptake of the anionic dye. Adsorption isotherm models suggested a monolayer adsorption was predominant. The mean free energy of adsorption (E(DR)) was found to have values between 8 and 16 kJ mol(-1) which suggests that an electrostatic mechanism of adsorption predominated over other underlying mechanisms. The adsorption process was also found to be spontaneous, with increasing negative free energy values observed at higher temperatures. Chemisorption process was supported by the changes in enthalpy above 40 kJ mol(-1) and by the results of desorption studies. This new adsorbent was also reusable and regenerable over four successive adsorption-desorption cycles. The single stage adsorber design revealed that PLC can be applicable as an effective biosorbent for the treatment of industrial effluents containing EY dye. PMID:25256550

  4. Wastewater treatment by batch adsorption method onto micro-particles of dried Withania frutescens plant as a new adsorbent.

    PubMed

    Chiban, Mohamed; Soudani, Amina; Sinan, Fouad; Persin, Michel

    2012-03-01

    A new adsorbent for removing metallic elements, nitrate and phosphate ions from municipal and industrial wastewaters has been investigated. This new adsorbent consists of micro-particles of dried Withania frutescens plant (<500 μm). Batch experiments were conducted to evaluate the removal of metallic elements and anions from raw wastewaters by W. frutescens particles. The results show that the micro-particles of W. frutescens plant presented a good adsorption of metallic elements, nitrate and phosphate ions from both real wastewaters. This adsorption increased with increasing of contact time. The percentage of metallic elements removal from industrial wastewater by W. frutescens plant was 98 ≈ 99% for Pb(II), 92 ≈ 93% for Cd(II), 91 ≈ 92% for Cu(II) and 92 ≈ 93% for Zn(II). The maximum adsorption capacity was dependent on the type of ions. The results also indicate that the values of chemical oxygen demand (COD) decrease after the contact with W. frutescens particles. Based on the results it can be concluded that the dried W. frutescens plant appears to be an economical and environmentally friendly material for wastewater treatment. PMID:21803480

  5. Effects of adsorbents and copper(II) on activated sludge microorganisms and sequencing batch reactor treatment process.

    PubMed

    Ong, S A; Lim, P E; Seng, C E

    2003-10-31

    Wastewater treatment systems employing simultaneous adsorption and biodegradation processes have proven to be effective in treating toxic pollutants present in industrial wastewater. The objective of this study is to evaluate the effect of Cu(II) and the efficacy of the powdered activated carbon (PAC) and activated rice husk (ARH) in reducing the toxic effect of Cu(II) on the activated sludge microorganisms. The ARH was prepared by treatment with concentrated nitric acid for 15 h at 60-65 degrees C. The sequencing batch reactor (SBR) systems were operated with FILL, REACT, SETTLE, DRAW and IDLE modes in the ratio of 0.5:3.5:1:0.75:0.25 for a cycle time of 6 h. The Cu(II) and COD removal efficiency were 90 and 85%, respectively, in the SBR system containing 10 mg/l Cu(II) with the addition of 143 mg/l PAC or 1.0 g PAC per cycle. In the case of 715 mg/l ARH or 5.0 g ARH per cycle addition, the Cu(II) and COD removal efficiency were 85 and 92%, respectively. ARH can be used as an alternate adsorbent to PAC in the simultaneous adsorption and biodegradation wastewater treatment process for the removal of Cu(II). The specific oxygen uptake rate (SOUR) and kinetic studies show that the addition of PAC and ARH reduce the toxic effect of Cu(II) on the activated sludge microorganisms. PMID:14573344

  6. Agro-industrial waste: a low cost adsorbent for effective removal of 4-chloro-2-methylphenoxyacetic acid herbicide in batch and packed bed modes.

    PubMed

    Deokar, Sunil K; Mandavgane, Sachin A; Kulkarni, Bhaskar D

    2016-08-01

    The present work describes the aqueous phase removal of 4-chloro-2-methylphenoxyacetic acid herbicide by rice husk ash (RHA) using batch and packed bed adsorption techniques. The effects of dosage, initial concentration, time, pH, temperature, and particle size of adsorbent in batch compared with effects of influent concentration, flow rate, and bed height in packed bed were studied. The particle size effect reveals that the removal is dependent on chemical composition (silica and carbon content) together with BET surface area of RHA. The aptness of Langmuir isotherm to batch data indicates the favorable adsorption whereas that of Temkin isotherm informs the heterogeneous nature of RHA. The kinetics of adsorption follows the pseudo-second order and Elovich models while thermodynamics of process indicates the exothermic adsorption. Among the models applied in packed bed study, the deactivation kinetic, Yoon-Nelson and bed depth service time (BDST) models are suitable to explain the packed bed adsorption. The adsorption capacity of RHA in packed bed study is found greater than that in batch. The adsorption capacity of RHA determined by the BDST model is 3019 mg/L for 90 % saturation of bed. The adsorption capacity of RHA based on weight is ∼2.3 times and that based on surface area is ∼55.55 times greater than that of granular activated carbon. PMID:27151241

  7. Amino-functionalized mesoporous MCM-41 silica as an efficient adsorbent for water treatment: batch and fixed-bed column adsorption of the nitrate anion

    NASA Astrophysics Data System (ADS)

    Ebrahimi-Gatkash, Mehdi; Younesi, Habibollah; Shahbazi, Afsaneh; Heidari, Ava

    2015-11-01

    In the present study, amino-functionalized Mobil Composite Material No. 41 (MCM-41) was used as an adsorbent to remove nitrate anions from aqueous solutions. Mono-, di- and tri-amino functioned silicas (N-MCM-41, NN-MCM-41 and NNN-MCM-41) were prepared by post-synthesis grafting method. The samples were characterized by means of X-ray powder diffraction, FTIR spectroscopy, thermogravimetric analysis, scanning electron microscopy and nitrogen adsorption-desorption. The effects of pH, initial concentration of anions, and adsorbent loading were examined in batch adsorption system. Results of adsorption experiments showed that the adsorption capacity increased with increasing adsorbent loading and initial anion concentration. It was found that the Langmuir mathematical model indicated better fit to the experimental data than the Freundlich. According to the constants of the Langmuir equation, the maximum adsorption capacity for nitrate anion by N-MCM-41, NN-MCM-41 and NNN-MCM-41 was found to be 31.68, 38.58 and 36.81 mg/g, respectively. The adsorption kinetics were investigated with pseudo-first-order and pseudo-second-order model. Adsorption followed the pseudo-second-order rate kinetics. The coefficients of determination for pseudo-second-order kinetic model are >0.99. For continuous adsorption experiments, NNN-MCM-41 adsorbent was used for the removal of nitrate anion from solutions. Breakthrough curves were investigated at different bed heights, flow rates and initial nitrate anion concentrations. The Thomas and Yan models were utilized to calculate the kinetic parameters and to predict the breakthrough curves of different bed height. Results from this study illustrated the potential utility of these adsorbents for nitrate removal from water solution.

  8. Cloning, expression, characterization and crystallization of BRP39, a signalling glycoprotein expressed during mammary gland apoptosis.

    PubMed

    Mohanty, Ashok K; Fisher, Andrew J; Yu, Zhihao; Pradeep, Mangottil A; Janjanam, Jagdeesh; Kaushik, Jai K

    2009-04-01

    Breast regression protein (BRP39) is a glycoprotein, which is expressed during mammary gland involution in mouse. The physiological function of BRP39 is not known. High levels of expression of BRP39 have also been associated with breast cancer development. In the present investigation a cDNA encoding rBRP39 (recombinant BRP39) was cloned by PCR techniques. It consists of 1,143 nucleotides and encodes an open reading frame of 381 amino acid residues including a signal sequence of 21 amino acids. Recombinant BRP39 was produced in E. coli in a soluble form at low temperature (15 degrees C). Expression and purification of rBRP39 was confirmed by western blot analysis. Purified rBRP39 showed high chitin-binding activity but no chitinase activity. The lack of chitinase activity may be attributed to the mutation of critical active site residue Glu120 to Leu120 and Asp118 to Ala118 in BRP39. However, a mutant in which the residue was reverted back to Glu, by site directed mutagenesis, displayed no chitinase activity. Purified recombinant BRP39 was crystallized and the crystals diffracted X-rays to 2.8A resolution. The crystals belonged to the space group C2 with unit cell parameters a=130.4A, b=81.3A, c=229.2A, beta=105.9 degrees. The structure refinement is in progress. PMID:19041398

  9. Fed-batch cultivation of the marine bacterium Sulfitobacter pontiacus using immobilized substrate and purification of sulfite oxidase by application of membrane adsorber technology.

    PubMed

    Muffler, Kai; Ulber, Roland

    2008-03-01

    Sulfitobacter pontiacus, a gram-negative heterotrophic bacterium isolated from the Black Sea is well known to produce a soluble AMP-independent sulfite oxidase (sulfite: acceptor oxidoreductase) of high activity. Such an enzyme can be of great help in establishing biosensor systems for detection of sulfite in food and beverages considering the high sensitivity of biosensors and the increasing demand for such biosensor devices. For obtaining efficient amounts of the enzyme, an induction of its biosynthesis by supplementing sufficient concentrations of sodium sulfite to the fermentation broth is required. Owing to the fact that a high initial concentration of sodium sulfite decreases dramatically the enzyme expression, different fed-batch strategies can be applied to circumvent such inhibition or repression of the enzyme respectively. By the use of sulfite species immobilized in polyvinyl alcohol gels, an approach to the controlled and continuous feeding of sulfite to the cultivation media could be established to diminish inhibitory concentrations. Furthermore, the purification of the enzyme is described by using membrane adsorber technology. PMID:17705251

  10. Pine bark as bio-adsorbent for Cd, Cu, Ni, Pb and Zn: batch-type and stirred flow chamber experiments.

    PubMed

    Cutillas-Barreiro, L; Ansias-Manso, L; Fernández-Calviño, D; Arias-Estévez, M; Nóvoa-Muñoz, J C; Fernández-Sanjurjo, M J; Álvarez-Rodríguez, E; Núñez-Delgado, A

    2014-11-01

    The objective of this work was to determine the retention of five metals on pine bark using stirred flow and batch-type experiments. Resulting from batch-type kinetic experiments, adsorption was rapid, with no significant differences for the various contact times. Adsorption was between 98 and 99% for Pb(2+), 83-84% for Cu(2+), 78-84% for Cd(2+), 77-83% for Zn(2+), and 70-75% for Ni(2+), and it was faster for low concentrations, with Pb suffering the highest retention, followed by Cu, Cd, Ni and Zn. The fitting to the Freundlich and Langmuir models was satisfactory. Desorption increased in parallel to the added concentrations, with Pb always showing the lowest levels. Stirred flow chamber experiments showed strong hysteresis for Pb and Cu, sorption being mostly irreversible. The differences affecting the studied heavy metals are mainly due to different affinity for the adsorption sites. Pine bark can be used to effectively remove Pb and Cu from polluted environments. PMID:24973614

  11. 77 FR 12450 - Airworthiness Directives; BRP-Powertrain GmbH & Co KG Rotax Reciprocating Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-01

    ...We are adopting a new airworthiness directive (AD) for BRP- Powertrain GmbH & Co KG Rotax 912 S2, 912 S3, and 914 F2 reciprocating engines. This AD requires performing a one-time inspection of the oil system for leaks and a torque check of the oil pump attachment bolts, and if leaks are detected, performing a one-time inspection of the oil pump and engine valve train, on certain serial number......

  12. Homogeneity of the geochemical reference material BRP-1 (paraná basin basalt) and assessment of minimum mass

    USGS Publications Warehouse

    Cotta, Aloisio J. B.; Enzweiler, Jacinta; Wilson, Stephen A.; Perez, Carlos A.; Nardy, Antonio J. R.; Larizzatti, Joao H.

    2007-01-01

    Reference materials (RM) are required for quantitative analyses and their successful use is associated with the degree of homogeneity, and the traceability and confidence limits of the values established by characterisation. During the production of a RM, the chemical characterisation can only commence after it has been demonstrated that the material has the required level of homogeneity. Here we describe the preparation of BRP-1, a proposed geochemical reference material, and the results of the tests to evaluate its degree of homogeneity between and within bottles. BRP-1 is the first of two geochemical RM being produced by Brazilian institutions in collaboration with the United States Geological Survey (USGS) and the International Association of Geoanalysts (IAG). Two test portions of twenty bottles of BRP-1 were analysed by wavelength dispersive-XRF spectrometry and major, minor and eighteen trace elements were determined. The results show that for most of the investigated elements, the units of BRP-1 were homogeneous at conditions approximately three times more rigorous than those strived for by the test of “sufficient homogeneity”. Furthermore, the within bottle homogeneity of BRP-1 was evaluated using small beam (1 mm2) synchrotron radiation XRF spectrometry and, for comparison, the USGS reference materials BCR-2 and GSP-2 were also evaluated. From our data, it has been possible to assign representative minimum masses for some major constituents (1 mg) and for some trace elements (1-13 mg), except Zr in GSP-2, for which test portions of 74 mg are recommended.

  13. The novel benzimidazole derivative BRP-7 inhibits leukotriene biosynthesis in vitro and in vivo by targeting 5-lipoxygenase-activating protein (FLAP)

    PubMed Central

    Pergola, C; Gerstmeier, J; Mönch, B; Çalışkan, B; Luderer, S; Weinigel, C; Barz, D; Maczewsky, J; Pace, S; Rossi, A; Sautebin, L; Banoglu, E; Werz, O

    2014-01-01

    BACKGROUND AND PURPOSE Leukotrienes (LTs) are inflammatory mediators produced via the 5-lipoxygenase (5-LOX) pathway and are linked to diverse disorders, including asthma, allergic rhinitis and cardiovascular diseases. We recently identified the benzimidazole derivative BRP-7 as chemotype for anti-LT agents by virtual screening targeting 5-LOX-activating protein (FLAP). Here, we aimed to reveal the in vitro and in vivo pharmacology of BRP-7 as an inhibitor of LT biosynthesis. EXPERIMENTAL APPROACH We analysed LT formation and performed mechanistic studies in human neutrophils and monocytes, in human whole blood (HWB) and in cell-free assays. The effectiveness of BRP-7 in vivo was evaluated in rat carrageenan-induced pleurisy and mouse zymosan-induced peritonitis. KEY RESULTS BRP-7 potently suppressed LT formation in neutrophils and monocytes and this was accompanied by impaired 5-LOX co-localization with FLAP. Neither the cellular viability nor the activity of 5-LOX in cell-free assays was affected by BRP-7, indicating that a functional FLAP is needed for BRP-7 to inhibit LTs, and FLAP bound to BRP-7 linked to a solid matrix. Compared with the FLAP inhibitor MK-886, BRP-7 did not significantly inhibit COX-1 or microsomal prostaglandin E2 synthase-1, implying the selectivity of BRP-7 for FLAP. Finally, BRP-7 was effective in HWB and impaired inflammation in vivo, in rat pleurisy and mouse peritonitis, along with reducing LT levels. CONCLUSIONS AND IMPLICATIONS BRP-7 potently suppresses LT biosynthesis by interacting with FLAP and exhibits anti-inflammatory effectiveness in vivo, with promising potential for further development. PMID:24641614

  14. The Arabidopsis transcription factor IIB-related protein BRP4 is involved in the regulation of mitotic cell-cycle progression during male gametogenesis

    PubMed Central

    Hu, Yuxin

    2014-01-01

    Male gametogenesis in angiosperms involves two rounds of mitosis that are essential for the generation of two sperm cells to achieve double fertilization, a distinct event in the sexual reproduction of flowering plants. Precise regulation of mitosis during male gametogenesis is critically important for the establishment of the male germline. However, the molecular mechanisms underlying mitotic division during male gametophyte development have not been characterized fully. Here, we report that the Arabidopsis transcription initiation factor TFIIB-related protein BRP4 is involved in the regulation of mitotic cell-cycle progression during male gametogenesis. BRP4 was expressed predominately in developing male gametophytes. Knockdown expression of BRP4 by a native promoter-driven RNA interference construct in Arabidopsis resulted in arrest of the mitotic progression of male gametophytes, leading to a defect in pollen development. Moreover, we showed that the level of expression of a gene encoding a subunit of the origin recognition complex, ORC6, was decreased in BRP4 knockdown plants, and that the ORC6 knockdown transgenic plants phenocopied the male gametophyte defect observed in BRP4 knockdown plants, suggesting that ORC6 acts downstream of BRP4 to mediate male mitotic progression. Taken together, our results reveal that BRP4 plays an important role in the regulation of mitotic cell-cycle progression during male gametogenesis. PMID:24723406

  15. REUSABLE ADSORBENTS FOR DILUTE SOLUTIONS SEPARATION. 6. BATCH AND CONTINUOUS REACTORS FOR ADSORPTION AND DEGRADATION OF 1,2-DICHLOROBENZENE FROM DILUTE WASTEWATER STREAMS USING TITANIA AS A PHOTOCATALYST. (R828598C753)

    EPA Science Inventory

    Two types of external lamp reactors were investigated for the titania catalyzed photodegradation of 1,2-dichlorobenzene (DCB) from a dilute water stream. The first one was a batch mixed slurry reactor and the second one was a semi-batch reactor with continuous feed recycle wit...

  16. Synthesis and biological evaluation of C(5)-substituted derivatives of leukotriene biosynthesis inhibitor BRP-7.

    PubMed

    Levent, Serkan; Gerstmeier, Jana; Olgaç, Abdurrahman; Nikels, Felix; Garscha, Ulrike; Carotti, Andrea; Macchiarulo, Antonio; Werz, Oliver; Banoglu, Erden; Çalışkan, Burcu

    2016-10-21

    Pharmacological intervention with 5-lipoxygenase (5-LO) pathway leading to suppression of leukotriene (LT) biosynthesis is a clinically validated strategy for treatment of respiratory and cardiovascular diseases such as asthma and atherosclerosis. Here we describe the synthesis of a series of C(5)-substituted analogues of the previously described 5-LO-activating protein (FLAP) inhibitor BRP-7 (IC50 = 0.31 μM) to explore the effects of substitution at the C(5)-benzimidazole (BI) ring as a strategy to increase the potency against FLAP-mediated 5-LO product formation. Incorporation of polar substituents on the C(5) position of the BI core, exemplified by compound 11 with a C(5)-nitrile substituent, significantly enhances the potency for suppression of 5-LO product synthesis in human neutrophils (IC50 = 0.07 μM) and monocytes (IC50 = 0.026 μM). PMID:27423639

  17. Adsorbent phosphates

    NASA Technical Reports Server (NTRS)

    Watanabe, S.

    1983-01-01

    An adsorbent which uses as its primary ingredient phosphoric acid salts of zirconium or titanium is presented. Production methods are discussed and several examples are detailed. Measurements of separating characteristics of some gases using the salts are given.

  18. Metagenomic identification of a novel salt tolerance gene from the human gut microbiome which encodes a membrane protein with homology to a brp/blh-family β-carotene 15,15'-monooxygenase.

    PubMed

    Culligan, Eamonn P; Sleator, Roy D; Marchesi, Julian R; Hill, Colin

    2014-01-01

    The human gut microbiome consists of at least 3 million non-redundant genes, 150 times that of the core human genome. Herein, we report the identification and characterisation of a novel stress tolerance gene from the human gut metagenome. The locus, assigned brpA, encodes a membrane protein with homology to a brp/blh-family β-carotene monooxygenase. Cloning and heterologous expression of brpA in Escherichia coli confers a significant salt tolerance phenotype. Furthermore, when cultured in the presence of exogenous β-carotene, cell pellets adopt a red/orange pigmentation indicating the incorporation of carotenoids in the cell membrane. PMID:25058308

  19. Batch-to-batch reproducibility of Transferon™.

    PubMed

    Medina-Rivero, Emilio; Merchand-Reyes, Giovanna; Pavón, Lenin; Vázquez-Leyva, Said; Pérez-Sánchez, Gilberto; Salinas-Jazmín, Nohemí; Estrada-Parra, Sergio; Velasco-Velázquez, Marco; Pérez-Tapia, Sonia Mayra

    2014-01-01

    Human dialyzable leukocyte extracts (DLEs) are heterogeneous mixtures of low-molecular-weight peptides that modulate immune responses in various diseases. Due their complexity, standardized methods to identify their physicochemical properties and determine that production batches are biologically active must be established. We aimed to develop and validate a size exclusion ultra performance chromatographic (SE-UPLC) method to characterize Transferon™, a DLE that is produced under good manufacturing practices (GMPs). We analyzed an internal human DLE standard and 10 representative batches of Transferon™, all of which had a chromatographic profile characterized by 8 main peaks and a molecular weight range between 17.0 and 0.2kDa. There was high homogeneity between batches with regard to retention times and area percentages, varying by less than 0.2% and 30%, respectively, and the control chart was within 3 standard deviations. To analyze the biological activity of the batches, we studied the ability of Transferon™ to stimulate IFN-γ production in vitro. Transferon™ consistently induced IFN-γ production in Jurkat cells, demonstrating that this method can be included as a quality control step in releasing Transferon™ batches. Because all analyzed batches complied with the quality attributes that were evaluated, we conclude that the DLE Transferon™ is produced with high homogeneity. PMID:24099727

  20. The Arabidopsis acetylated histone-binding protein BRAT1 forms a complex with BRP1 and prevents transcriptional silencing

    PubMed Central

    Zhang, Cui-Jun; Hou, Xiao-Mei; Tan, Lian-Mei; Shao, Chang-Rong; Huang, Huan-Wei; Li, Yong-Qiang; Li, Lin; Cai, Tao; Chen, She; He, Xin-Jian

    2016-01-01

    Transposable elements and other repetitive DNA sequences are usually subject to DNA methylation and transcriptional silencing. However, anti-silencing mechanisms that promote transcription in these regions are not well understood. Here, we describe an anti-silencing factor, Bromodomain and ATPase domain-containing protein 1 (BRAT1), which we identified by a genetic screen in Arabidopsis thaliana. BRAT1 interacts with an ATPase domain-containing protein, BRP1 (BRAT1 Partner 1), and both prevent transcriptional silencing at methylated genomic regions. Although BRAT1 mediates DNA demethylation at a small set of loci targeted by the 5-methylcytosine DNA glycosylase ROS1, the involvement of BRAT1 in anti-silencing is largely independent of DNA demethylation. We also demonstrate that the bromodomain of BRAT1 binds to acetylated histone, which may facilitate the prevention of transcriptional silencing. Thus, BRAT1 represents a potential link between histone acetylation and transcriptional anti-silencing at methylated genomic regions, which may be conserved in eukaryotes. PMID:27273316

  1. The uranium from seawater program at PNNL: Overview of marine testing, adsorbent characterization, adsorbent durability, adsorbent toxicity, and deployment studies

    DOE PAGESBeta

    Gill, Gary A.; Kuo, Li -Jung; Janke, Christopher James; Park, Jiyeon; Jeters, Robert T.; Bonheyo, George T.; Pan, Horng -Bin; Wai, Chien; Khangaonkar, Tarang P.; Bianucci, Laura; et al

    2016-02-07

    at Woods Hole Oceanographic Institution with the ORNL AF1 adsorbent produced 15% and 55% higher adsorption capacities than observed at PNNL for column and flume testing, respectively. Variations in competing ions may be the explanation for the regional differences. In addition to marine testing, a number of other efforts are underway to characterize adsorbents and impacts of deployment on the marine environment. Highlights include: Hydrodynamic modelling predicts that a farm of adsorbent materials will likely have minimal effect on ocean currents and removal of uranium and other elements from seawater when densities are < 1800 braids/km2. A decrease in U adsorption capacity of up to 30% was observed after 42 days of exposure due to biofouling when the ORNL braided adsorbent AI8 was exposed to raw seawater in a flume in the presence of light. An identical raw seawater exposure with no light exposure showed little or no impact to adsorption capacity from biofouling. No toxicity was observed with column effluents of any absorbent materials tested to date. Toxicity could be induced with some non amidoxime-based absorbents only when the ratio of solid absorbent to test media was increased to highly unrealistic levels. Thermodynamic modeling of the seawater-amidoxime adsorbent was performed using the geochemical modeling program PHREEQC. Modeling of the binding of Ca, Mg, Fe, Ni, Cu, U, and V from batch interactions with seawater across a variety of concentrations of the amidoxime binding group reveal that when binding sites are limited (1 x 10-8 binding sites/kg seawater), vanadium heavily out-competes other ions for the amidoxime sites. In contrast, when binding sites are abundant magnesium and calcium dominate the total percentage of metals bound to the sorbent.« less

  2. The Uranium from Seawater Program at PNNL: Overview of marine testing, adsorbent characterization, adsorbent durability, adsorbent toxicity, and deployment studies

    SciTech Connect

    Gill, Gary; Kuo, Li-Jung; Janke, Christopher James; Park, Jiyeon; Jeters, Robert T; Bonheyo, George; Pan, Horng-Bin; Wai, Chien; Khangaonkar, Tarang P; Bianucci, Laura; Wood, Jordana; Warner, Marvin G; Peterson, Sonja; Abrecht, David; Mayes, Richard T; Tsouris, Costas; Oyola, Yatsandra; Strivens, Jonathan E.; Schlafer, Nicholas; Addleman, Shane R; Chouyyok, Wilaiwan; Das, Sadananda; Kim, Jungseung; Buesseler, Dr. Ken; Breier, Crystalline; D'Alessandro, Dr. Evan

    2016-01-01

    Oceanographic Institution with the ORNL AF1 adsorbent produced 15% and 55% higher adsorption capacities than observed at PNNL for column and flume testing, respectively. Variations in competing ions may be the explanation for the regional differences. In addition to marine testing, a number of other efforts are underway to characterize adsorbents and impacts of deployment on the marine environment. Highlights include: Hydrodynamic modelling predicts that a farm of adsorbent materials will likely have minimal effect on ocean currents and removal of uranium and other elements from seawater when densities are < 1800 braids/km2. A decrease in U adsorption capacity of up to 30% was observed after 42 days of exposure due to biofouling when the ORNL braided adsorbent AI8 was exposed to raw seawater in a flume in the presence of light. An identical raw seawater exposure with no light exposure showed little or no impact to adsorption capacity from biofouling. No toxicity was observed with column effluents of any absorbent materials tested to date. Toxicity could be induced with some non amidoxime-based absorbents only when the ratio of solid absorbent to test media was increased to highly unrealistic levels. Thermodynamic modeling of the seawater-amidoxime adsorbent was performed using the geochemical modeling program PHREEQC. Modeling of the binding of Ca, Mg, Fe, Ni, Cu, U, and V from batch interactions with seawater across a variety of concentrations of the amidoxime binding group reveal that when binding sites are limited (1 x 10-8 binding sites/kg seawater), vanadium heavily out-competes other ions for the amidoxime sites. In contrast, when binding sites are abundant magnesium and calcium dominate the total percentage of metals bound to the sorbent.

  3. 12 Batch coalescing studies

    SciTech Connect

    Kourbanis, I.; Wildman, D.; /Fermilab

    1995-01-01

    The purpose of the study was to identify and correct the problems in the 12 batch coalescing. The final goal is to be able to coalesce 12 booster batches of 11 bunches each into 12 bunches spaced at 21 buckets apart with an average intensity of 200 E9 ppb.

  4. Application of quantum descriptors for predicting adsorption performance of starch and cyclodextrin adsorbents.

    PubMed

    Okoli, Chukwunonso Peter; Guo, Qing Jun; Adewuyi, Gregory Olufemi

    2014-01-30

    Adsorption trend of aromatic compounds on epichlorohydrin (EPI), 1,6-hexamethylene diisocyanate (HDI), and 4,4-methylene diphenyl diisocyanate (MDI) cross-linked starch and cyclodextrin adsorbents were comparatively studied by density functional theorem (DFT) based interaction descriptors and batch adsorption studies. The DFT quantum chemical descriptors predicted adsorption trend of MDI adsorbents>HDI adsorbents>EPI adsorbents. The values of the fractional number of electrons transferred (ΔN) for all the studied adsorbent-adsorbate pair were negative, indicating that the adsorbents were electron donors in the studied adsorption interaction. The batch adsorption performance for the studied cross-linked adsorbents was in agreement with the DFT predictions. Energy gap, chemical hardness, and softness showed good linear correlation (R(2)=0.8,073 ± 0.2259) to the batch adsorption performance for most of the studied adsorbent-adsorbate pairs. The present study demonstrated that DFT quantum chemical parameters are suitable adsorption descriptors for predicting adsorption performance of cross-linked adsorbents. PMID:24299747

  5. Software for batch farms

    SciTech Connect

    Ian Bird; Bryan Hess; Andy Kowalski

    2000-02-01

    Over the past few years, LSF has become a standard for job management on batch farms. However, there are many instances where it cannot be deployed for a variety of reasons. In large farms the cost may be prohibitive for the set of features actually used; small university groups who wish to clone the farms and software of larger laboratories often have constraints which preclude the use of LSF. This paper discusses a generic interface developed at Jefferson Lab to provide a set of common services to the user, while using any one of a variety of underlying batch management software products. Initially the system provides an interface to LSF and an alternative--Portable Batch System (PBS) developed by NASA and freely available in source form. It is straightforward to extend this to other systems. Such a generic interface allows users to move from one location to another and run their jobs with no modification, and by extension provides a framework for a ''global'' batch system where jobs submitted at one site may be transparently executed at another. The interface also provides additional features not found in the underlying batch software. Being written in Java, the client can be easily installed anywhere and allows for authenticated remote job submission and manipulation, including a web interface. This paper will also discuss the problem of keeping a large batch farm occupied with work without waiting for slow tape access. The use of file caching, pre-staging of files from tape and the interconnection with the batch system will be discussed. As well as automated techniques, the provision of appropriate information to the user to allow optimization should not be overlooked.

  6. Debiasing Crowdsourced Batches

    PubMed Central

    Zhuang, Honglei; Parameswaran, Aditya; Roth, Dan; Han, Jiawei

    2015-01-01

    Crowdsourcing is the de-facto standard for gathering annotated data. While, in theory, data annotation tasks are assumed to be attempted by workers independently, in practice, data annotation tasks are often grouped into batches to be presented and annotated by workers together, in order to save on the time or cost overhead of providing instructions or necessary background. Thus, even though independence is usually assumed between annotations on data items within the same batch, in most cases, a worker's judgment on a data item can still be affected by other data items within the batch, leading to additional errors in collected labels. In this paper, we study the data annotation bias when data items are presented as batches to be judged by workers simultaneously. We propose a novel worker model to characterize the annotating behavior on data batches, and present how to train the worker model on annotation data sets. We also present a debiasing technique to remove the effect of such annotation bias from adversely affecting the accuracy of labels obtained. Our experimental results on both synthetic data and real-world data demonstrate the effectiveness of our proposed method. PMID:26713175

  7. GIDEP Batching Tool

    NASA Technical Reports Server (NTRS)

    Fong, Danny; Odell,Dorice; Barry, Peter; Abrahamian, Tomik

    2008-01-01

    This software provides internal, automated search mechanics of GIDEP (Government- Industry Data Exchange Program) Alert data imported from the GIDEP government Web site. The batching tool allows the import of a single parts list in tab-delimited text format into the local JPL GIDEP database. Delimiters from every part number are removed. The original part numbers with delimiters are compared, as well as the newly generated list without the delimiters. The two lists run against the GIDEP imports, and output any matches. This feature only works with Netscape 2.0 or greater, or Internet Explorer 4.0 or greater. The user selects the browser button to choose a text file to import. When the submit button is pressed, this script will import alerts from the text file into the local JPL GIDEP database. This batch tool provides complete in-house control over exported material and data for automated batch match abilities. The batching tool has the ability to match capabilities of the parts list to tables, and yields results that aid further research and analysis. This provides more control over GIDEP information for metrics and reports information not provided by the government site. This software yields results quickly and gives more control over external data from the government site in order to generate other reports not available from the external source. There is enough space to store years of data. The program relates to risk identification and management with regard to projects and GIDEP alert information encompassing flight parts for space exploration.

  8. Molecular Adsorber Coating

    NASA Technical Reports Server (NTRS)

    Straka, Sharon; Peters, Wanda; Hasegawa, Mark; Hedgeland, Randy; Petro, John; Novo-Gradac, Kevin; Wong, Alfred; Triolo, Jack; Miller, Cory

    2011-01-01

    A document discusses a zeolite-based sprayable molecular adsorber coating that has been developed to alleviate the size and weight issues of current ceramic puck-based technology, while providing a configuration that more projects can use to protect against degradation from outgassed materials within a spacecraft, particularly contamination-sensitive instruments. This coating system demonstrates five times the adsorption capacity of previously developed adsorber coating slurries. The molecular adsorber formulation was developed and refined, and a procedure for spray application was developed. Samples were spray-coated and tested for capacity, thermal optical/radiative properties, coating adhesion, and thermal cycling. Work performed during this study indicates that the molecular adsorber formulation can be applied to aluminum, stainless steel, or other metal substrates that can accept silicate-based coatings. The coating can also function as a thermal- control coating. This adsorber will dramatically reduce the mass and volume restrictions, and is less expensive than the currently used molecular adsorber puck design.

  9. Structural Identification of Modified Amino Acids on the Interface between EPO and Its Receptor from EPO BRP, Human Recombinant Erythropoietin by LC/MS Analysis

    PubMed Central

    Song, Kwang-Eun; Byeon, Jaehee; Moon, Dae-Bong; Kim, Hyong-Ha; Choi, Yoo-Joo; Suh, Jung-Keun

    2014-01-01

    Protein modifications of recombinant pharmaceuticals have been observed both in vitro and in vivo. These modifications may result in lower efficacy, as well as bioavailability changes and antigenicity among the protein pharmaceuticals. Therefore, the contents of modification should be monitored for the quality and efficacy of protein pharmaceuticals. The interface of EPO and its receptor was visualized, and potential amino acids interacting on the interface were also listed. Two different types of modifications on the interface were identified in the preparation of rHu-EPO BRP. A UPLC/Q-TOF MS method was used to evaluate the modification at those variants. The modification of the oxidized variant was localized on the Met54 and the deamidated variants were localized on the Asn47 and Asn147. The extent of oxidation at Met54 was 3.0% and those of deamidation at Asn47 and Asn147 were 2.9% and 4.8%, respectively. PMID:25284312

  10. Regenerative adsorbent heat pump

    NASA Technical Reports Server (NTRS)

    Jones, Jack A. (Inventor)

    1991-01-01

    A regenerative adsorbent heat pump process and system is provided which can regenerate a high percentage of the sensible heat of the system and at least a portion of the heat of adsorption. A series of at least four compressors containing an adsorbent is provided. A large amount of heat is transferred from compressor to compressor so that heat is regenerated. The process and system are useful for air conditioning rooms, providing room heat in the winter or for hot water heating throughout the year, and, in general, for pumping heat from a lower temperature to a higher temperature.

  11. Biodegradable metal adsorbent synthesized by graft polymerization onto nonwoven cotton fabric

    NASA Astrophysics Data System (ADS)

    Sekine, Ayako; Seko, Noriaki; Tamada, Masao; Suzuki, Yoshio

    2010-01-01

    A fibrous adsorbent for Hg ions was synthesized by radiation-induced emulsion graft polymerization of glycidyl methacrylate (GMA) onto a nonwoven cotton fabric and subsequent chemical modification. The optimal pre-irradiation dose for initiation of the graft polymerization of GMA, which minimized the effects of radiation damage on the mechanical strength of the nonwoven cotton fabric, was found to be 10 kGy. The GMA-grafted nonwoven cotton fabric was subsequently modified with ethylenediamine (EDA) or diethylenetriamine (DETA) to obtain a Hg adsorbent. The resulting amine-type adsorbents were evaluated for batch and continuous adsorption of Hg. In batch adsorption, the distribution coefficients of Hg reached 1.9×10 5 and 1.0×10 5 for EDA- and DETA-type adsorbents, respectively. A column packed with EDA-type adsorbent removed Hg from 1.8 ppm Hg solution at a space velocity of 100 h -1, which corresponds to 16,000 times the volume of the packed adsorbent. The adsorbed Hg on the EDA-type adsorbent could be completely eluted by 1 M HCl solution. A microbial oxidative degradation test revealed that the EDA-type adsorbent is biodegradable.

  12. Adsorbent and adsorbent bed for materials capture and separation processes

    SciTech Connect

    Liu, Wei

    2011-01-25

    A method device and material for performing adsorption wherein a fluid mixture is passed through a channel in a structured adsorbent bed having a solid adsorbent comprised of adsorbent particles having a general diameter less than 100 um, loaded in a porous support matrix defining at least one straight flow channel. The adsorbent bed is configured to allow passage of a fluid through said channel and diffusion of a target material into said adsorbent under a pressure gradient driving force. The targeted molecular species in the fluid mixture diffuses across the porous support retaining layer, contacts the adsorbent, and adsorbs on the adsorbent, while the remaining species in the fluid mixture flows out of the channel.

  13. Evaluation of a cesium adsorbent grafted with ammonium 12-molybdophosphate

    NASA Astrophysics Data System (ADS)

    Shibata, Takuya; Seko, Noriaki; Amada, Haruyo; Kasai, Noboru; Saiki, Seiichi; Hoshina, Hiroyuki; Ueki, Yuji

    2016-02-01

    A fibrous cesium (Cs) adsorbent was developed using radiation-induced graft polymerization with a cross-linked structure containing a highly stable adsorption ligand. The ligand, ammonium 12-molybdophosphate (AMP), was successfully introduced onto the fibrous polyethylene trunk material. The resulting Cs adsorbent contained 36% nonwoven fabric polyethylene (NFPE), 1% AMP, 2% triallyl isocyanurate (TAIC) and 61% glycidyl methacrylate (GMA). The adsorbent's Cs adsorption capacity was evaluated using batch and column tests. It was determined that the adsorbent could be used in a wide pH range. The amount of desorbed molybdenum, which can be used as an estimate for AMP stability on the Cs adsorbent, was minimized at the standard drinking water pH range of 5.8-8.6. Based from the inspection on the adherence of these results to the requirements set forth by the Food Sanitation Act by a third party organization, it can be concluded that the developed Cs adsorbent can be safely utilized for drinking water.

  14. Evaluation of pharmaceuticals removal by sewage sludge-derived adsorbents with rapid small-scale column tests

    NASA Astrophysics Data System (ADS)

    Zhang, P.; Ding, R.; Wallace, R.; Bandosz, T.

    2015-12-01

    New composite adsorbents were developed by pyrolyzing sewage sludge and fish waste (75:25 or 90:10 dry mass ratio) at 650 oC and 950 oC. Batch adsorption experiments demonstrated that the composite adsorbents were able to adsorb a wide range of organic contaminants (volatile organic compounds, pharmaceuticals and endocrine disrupting compounds (EDCs), and nitrosamine disinfection byproducts) with high capacities. Here we further examine the performance of the adsorbents for the simultaneous removal of 8 pharmaceuticals and EDCs with rapid small-scale column tests (RSSCT). Results show that the order of breakthrough in RSSCT is in general consistent with the affinity determined via batch tests. As expected, the maximum amount of adsorption for each compound obtained from RSSCT is identical to or less than that obtained from batch tests (with only one exception), due to adsorption kinetics. However, despite the very different input concentration (1 mg/L vs. 100 mg/L) and contact time (2 min empty bed contact time vs. 16 hour equilibrium time) used in RSSCT and batch tests, the maximum amount of pharmaceuticals and EDCs adsorbed under RSSCT is still about one half of that under equilibrium batch tests, validating the approach of using batch tests with much higher input concentrations to determine adsorption capacities. Results of a pilot-scale column test in a drinking water treatment plant for pharmaceuticals removal will also be presented.

  15. Enhanced encapsulation of metoprolol tartrate with carbon nanotubes as adsorbent

    NASA Astrophysics Data System (ADS)

    Garala, Kevin; Patel, Jaydeep; Patel, Anjali; Dharamsi, Abhay

    2011-12-01

    A highly water-soluble antihypertensive drug, metoprolol tartrate (MT), was selected as a model drug for preparation of multi-walled carbon nanotubes (MWCNTs)-impregnated ethyl cellulose (EC) microspheres. The present investigation was aimed to increase encapsulation efficiency of MT with excellent adsorbent properties of MWCNTs. The unique surface area, stiffness, strength and resilience of MWCNTs have drawn much anticipation as carrier for highly water-soluble drugs. Carbon nanotubes drug adsorbate (MWCNTs:MT)-loaded EC microspheres were further optimized by the central composite design of the experiment. The effects of independent variables (MWCNTs:MT and EC:adsorbate) were evaluated on responses like entrapment efficiency (EE) and t 50 (time required for 50% drug release). The optimized batch was compared with drug alone EC microspheres. The results revealed high degree of improvement in encapsulation efficiency for MWCNTs:MT-loaded EC microspheres. In vitro drug release study exhibited complete release form drug alone microspheres within 15 h, while by the same time only 50-60% drug was released for MWCNTs-impregnated EC microspheres. The optimized batch was further characterized by various instrumental analyses such as scanning electron microscopy, powder X-ray diffraction and differential scanning calorimetry. The results endorse encapsulation of MWCNTs:MT adsorbate inside the matrix of EC microspheres, which might have resulted in enhanced encapsulation and sustained effect of MT. Hence, MWCNTs can be utilized as novel carriers for extended drug release and enhanced encapsulation of highly water-soluble drug, MT.

  16. Progressing batch hydrolysis process

    DOEpatents

    Wright, John D.

    1986-01-01

    A progressive batch hydrolysis process for producing sugar from a lignocellulosic feedstock, comprising passing a stream of dilute acid serially through a plurality of percolation hydrolysis reactors charged with said feedstock, at a flow rate, temperature and pressure sufficient to substantially convert all the cellulose component of the feedstock to glucose; cooling said dilute acid stream containing glucose, after exiting the last percolation hydrolysis reactor, then feeding said dilute acid stream serially through a plurality of prehydrolysis percolation reactors, charged with said feedstock, at a flow rate, temperature and pressure sufficient to substantially convert all the hemicellulose component of said feedstock to glucose; and cooling the dilute acid stream containing glucose after it exits the last prehydrolysis reactor.

  17. Progressing batch hydrolysis process

    DOEpatents

    Wright, J.D.

    1985-01-10

    A progressive batch hydrolysis process is disclosed for producing sugar from a lignocellulosic feedstock. It comprises passing a stream of dilute acid serially through a plurality of percolation hydrolysis reactors charged with feed stock, at a flow rate, temperature and pressure sufficient to substantially convert all the cellulose component of the feed stock to glucose. The cooled dilute acid stream containing glucose, after exiting the last percolation hydrolysis reactor, serially fed through a plurality of pre-hydrolysis percolation reactors, charged with said feedstock, at a flow rate, temperature and pressure sufficient to substantially convert all the hemicellulose component of said feedstock to glucose. The dilute acid stream containing glucose is cooled after it exits the last prehydrolysis reactor.

  18. Utility of adsorbents in the purification of drinking water: a review of characterization, efficiency and safety evaluation of various adsorbents.

    PubMed

    Dubey, Shashi Prabha; Gopal, Krishna; Bersillon, J L

    2009-05-01

    Clean drinking water is one of the implicit requisites fora healthy human population. However the growing industrialization and extensive use of chemicals for various concerns, has increased the burden of unwanted pollutants in the drinking water of developing countries like India. The entry of potentially hazardous substances into the biota has been magnifying day by day. In the absence of a possible stoppage of these, otherwise, useful chemicals, the only way to maintain safer water bodies is to develop efficient purifying technologies. One such immensely beneficial procedure that has been in use is that of purification of water using 'adsorbents'. Indigenous minerals and natural plants products have potential for removing many pollutants viz. fluoride, arsenic, nitrate, heavy metals, pesticides as well as trihalomethanes. Adsorbents which are derived from carbon, alumina, zeolite, clay minerals, iron ores, industrial by products, and natural products viz. parts of the plants, herbs and algal biomass offer promising potential of removal. In the recent years attention has been paid to develop process involving screening/pretreatment/activation/impregnation using alkalies, acids, alum, lime, manganese dioxide, ferric chloride and other chemicals which are found to enhance their adsorbing efficiency. Chemical characterization of these adsorbents recapitulates the mechanism of the process. It is imperative to observe that capacities of the adsorbents may vary depending on the characteristics, chemical modifications and concentration of the individual adsorbent. Removal kinetics is found to be based on the experimental conditions viz. pH, concentration of the adsorbate, quantity of the adsorbent and temperature. It is suggested that isotherm model is suitable tool to assess the adsorption capacities in batch and column modes. Safety evaluation and risk assessment of the process/products may be useful to provide guidelines for its sustainable disposal. PMID:20120453

  19. Synthesis of arsenic graft adsorbents in pilot scale

    NASA Astrophysics Data System (ADS)

    Hoshina, Hiroyuki; Kasai, Noboru; Shibata, Takuya; Aketagawa, Yasushi; Takahashi, Makikatsu; Yoshii, Akihiro; Tsunoda, Yasuhiko; Seko, Noriaki

    2012-08-01

    Synthesis of arsenic (As) adsorbents in pilot scale was carried out with a synthesizing apparatus by radiation-induced graft polymerization of 2-hydroxyethyl methacrylate phosphoric acid monomer (PA), which consists of phosphoric acid mono- (50%) and di- (50%) ethyl methacrylate esters onto a nonwoven cotton fabric (NCF), and following chemical modification by contact with a zirconium (Zr) solution. The apparatus which was equipped with reaction tanks, a washing tank and a pump can produce up to 0.3 m×14 m size of the As(V) adsorbent in one reaction. A degree of grafting of 150% was obtained at an irradiation dose of 20 kGy with 5% of PA solution mixed with deionized water for 1 h at 40 °C. Finally, after Zr(IV) was loaded onto a NCF with 5 mmol/L of Zr(IV) solution, the graft adsorbent for the removal of As(V) was achieved in pilot-scale. The adsorbent which was synthesized in pilot scale was evaluated in batch mode adsorption with 1 ppm (mg/l) of As(V) solution for 2 h at room temperature. As a result, the adsorption capacity for As(V) was 0.02 mmol/g-adsorbent.

  20. Adsorbent Alkali Conditioning for Uranium Adsorption from Seawater. Adsorbent Performance and Technology Cost Evaluation

    SciTech Connect

    Tsouris, Costas; Mayes, Richard T.; Janke, Christopher James; Dai, Sheng; Das, S.; Liao, W. -P.; Kuo, Li-Jung; Wood, Jordana; Gill, Gary; Byers, Maggie Flicker; Schneider, Eric

    2015-09-30

    The Fuel Resources program of the Fuel Cycle Research and Development program of the Office of Nuclear Energy (NE) is focused on identifying and implementing actions to assure that nuclear fuel resources are available in the United States. An immense source of uranium is seawater, which contains an estimated amount of 4.5 billion tonnes of dissolved uranium. This unconventional resource can provide a price cap and ensure centuries of uranium supply for future nuclear energy production. NE initiated a multidisciplinary program with participants from national laboratories, universities, and research institutes to enable technical breakthroughs related to uranium recovery from seawater. The goal is to develop advanced adsorbents to reduce the seawater uranium recovery technology cost and uncertainties. Under this program, Oak Ridge National Laboratory (ORNL) has developed a new amidoxime-based adsorbent of high surface area, which tripled the uranium capacity of leading Japanese adsorbents. Parallel efforts have been focused on the optimization of the physicochemical and operating parameters used during the preparation of the adsorbent for deployment. A set of parameters that need to be optimized are related to the conditioning of the adsorbent with alkali solution, which is necessary prior to adsorbent deployment. Previous work indicated that alkali-conditioning parameters significantly affect the adsorbent performance. Initiated in 2014, this study had as a goal to determine optimal parameters such as base type and concentration, temperature, and duration of conditioning that maximize the uranium adsorption performance of amidoxime functionalized adsorbent, while keeping the cost of uranium production low. After base-treatment at various conditions, samples of adsorbent developed at ORNL were tested in this study with batch simulated seawater solution of 8-ppm uranium concentration, batch seawater spiked with uranium nitrate at 75-100 ppb uranium, and continuous

  1. Preparation of ferric-activated sludge-based adsorbent from biological sludge for tetracycline removal.

    PubMed

    Yang, Xin; Xu, Guoren; Yu, Huarong; Zhang, Zhao

    2016-07-01

    Ferric activation was novelly used to produce sludge-based adsorbent (SBA) from biological sludge through pyrolysis, and the adsorbents were applied to remove tetracycline from aqueous solution. The pyrolysis temperature and mass ratio (activator/dried sludge) greatly influenced the surface area and pore characteristics of SBA. Ferric activation could promote the porous structure development of adsorbents, and the optimum preparation conditions were pyrolysis temperature 750°C and mass ratio (activator/dried sludge) 0.5. In batch experiments, ferric-activated SBA showed a higher adsorption capacity for tetracycline than non-activated SBA, because the enhanced mesoporous structure favored the diffusion of tetracycline into the pores, the iron oxides and oxygen-containing functional groups in the adsorbents captured tetracycline by surface complexation. The results indicate that ferric activation is an effective approach for preparing adsorbents from biological sludge to remove tetracycline, providing a potential option for waste resource recovery. PMID:27038265

  2. Data-driven batch schuduling

    SciTech Connect

    Bent, John; Denehy, Tim; Arpaci - Dusseau, Remzi; Livny, Miron; Arpaci - Dusseau, Andrea C

    2009-01-01

    In this paper, we develop data-driven strategies for batch computing schedulers. Current CPU-centric batch schedulers ignore the data needs within workloads and execute them by linking them transparently and directly to their needed data. When scheduled on remote computational resources, this elegant solution of direct data access can incur an order of magnitude performance penalty for data-intensive workloads. Adding data-awareness to batch schedulers allows a careful coordination of data and CPU allocation thereby reducing the cost of remote execution. We offer here new techniques by which batch schedulers can become data-driven. Such systems can use our analytical predictive models to select one of the four data-driven scheduling policies that we have created. Through simulation, we demonstrate the accuracy of our predictive models and show how they can reduce time to completion for some workloads by as much as 80%.

  3. Batch compositions for cordierite ceramics

    DOEpatents

    Hickman, David L.

    1994-07-26

    Ceramic products consisting principally of cordierite and a method for making them are provided, the method employing batches comprising a mineral component and a chemical component, the mineral component comprising clay and talc and the chemical component consisting essentially of a combination of the powdered oxides, hydroxides, or hydrous oxides of magnesium, aluminum and silicon. Ceramics made by extrusion and firing of the batches can exhibit low porosity, high strength and low thermal expansion coefficients.

  4. Adsorbed Water Illustration

    NASA Technical Reports Server (NTRS)

    2008-01-01

    The Thermal and Electrical Conductivity Probe on NASA's Phoenix Mars Lander detected small and variable amounts of water in the Martian soil.

    In this schematic illustration, water molecules are represented in red and white; soil minerals are represented in green and blue. The water, neither liquid, vapor, nor solid, adheres in very thin films of molecules to the surfaces of soil minerals. The left half illustrates an interpretation of less water being adsorbed onto the soil-particle surface during a period when the tilt, or obliquity, of Mars' rotation axis is small, as it is in the present. The right half illustrates a thicker film of water during a time when the obliquity is greater, as it is during cycles on time scales of hundreds of thousands of years. As the humidity of the atmosphere increases, more water accumulates on mineral surfaces. Thicker films behave increasingly like liquid water.

    The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  5. Heavy metals and adsorbents effects on activated sludge microorganisms.

    PubMed

    Ong, S A; Lim, P E; Seng, C E

    2004-01-01

    The sorption of Cu(II) and Cd(II) from synthetic solution by powdered activated carbon (PAC), biomass, rice husk (RH) and activated rice husk (ARH) were investigate under batch conditions. After activated by concentrated nitric acid for 15 hours at 60-65 degrees C, the adsorption capacity for RH was increased. The adsorbents arranged in the increasing order of adsorption capacities to the Langmuir Q degree parameter were biomass > PAC > ARH > RH. The addition of adsorbents in base mix solution had increased the specific oxygen uptake rate (SOUR) activated sludge microorganisms with and without the presence of metals. The increased of SOUR were due to the ability of PAC and RH in reducing the inhibitory effect of metals on microorganisms and provide a reaction site between activated sludge microorganisms and substrates. PMID:15141467

  6. Arsenic sorption onto titanium dioxide, granular ferric hydroxide and activated alumina: batch and dynamic studies.

    PubMed

    Lescano, Maia R; Passalía, Claudio; Zalazar, Cristina S; Brandi, Rodolfo J

    2015-01-01

    The aim of this work was to evaluate and compare the efficiencies of three different adsorbents for arsenic (As) removal from water: titanium dioxide (TiO2), granular ferric hydroxide (GFH) and activated alumina (AA). Equilibrium experiments for dissolved arsenite and arsenate were carried out through batch tests. Freundlich and Langmuir isotherm models were adopted and their parameters were estimated by non-linear regressions. In addition, dynamic experiments were performed in mini fixed bed columns and breakthrough curves were obtained for each combination of sorbate/adsorbent. Experimental results obtained by column assays were compared with predictions of well-known breakthrough models (Bohart-Adams and Clark). Results indicate that As(V) is more easily adsorbed than As(III) for AA and GFH, while TiO2 has a similar behavior for both species. The titanium-based material is the most efficient adsorbent to carry out the process, followed by the GFH. PMID:25723069

  7. Uptake of uranium from seawater by amidoxime-based polymeric adsorbent marine testing

    SciTech Connect

    Tsouris, C.; Kim, J.; Oyola, Y.; Mayes, R.; Hexel, C.; Sostre Gonzalez, F.; Janke, C.; Dai, S.; Gill, G.; Kuo, L.J.; Wood, J.; Choe, K.Y.; Pourmand, A.; D'Alessandro, E.; Buesseler, K.; Pike, S.

    2013-07-01

    Amidoxime-based polymer adsorbents in the form of functionalized fibers were prepared at the Oak Ridge National Laboratory (ORNL) and screened in laboratory experiments, in terms of uranium uptake capacity, using spiked uranium solution and seawater samples. Batch laboratory experiments conducted with 5-gallon seawater tanks provided equilibrium information. Based on results from 5-gallon experiments, the best adsorbent was selected for field-testing of uranium adsorption from seawater. Flow-through column tests have been performed at different marine sites to investigate the uranium uptake rate and equilibrium capacity under diverse biogeochemistry. The maximum amount of uranium uptake from seawater tests at Sequim, WA, was 3.3 mg U/g adsorbent after eight weeks of contact of the adsorbent with seawater. This amount was three times higher than the maximum adsorption capacity achieved in this study by a leading adsorbent developed by the Japan Atomic Energy Agency (JAEA), which was 1.1 mg U/g adsorbent at equilibrium. The initial uranium uptake rate of the ORNL adsorbent was 2.6 times higher than that of the JAEA adsorbent under similar conditions. A mathematical model derived from the mass balance of uranium was employed to describe the data. (authors)

  8. MBASIC batch processor architectural overview

    NASA Technical Reports Server (NTRS)

    Reynolds, S. M.

    1978-01-01

    The MBASIC (TM) batch processor, a language translator designed to operate in the MBASIC (TM) environment is described. Features include: (1) a CONVERT TO BATCH command, usable from the ready mode; and (2) translation of the users program in stages through several levels of intermediate language and optimization. The processor is to be designed and implemented in both machine-independent and machine-dependent sections. The architecture is planned so that optimization processes are transparent to the rest of the system and need not be included in the first design implementation cycle.

  9. Physicochemical Characteristics of Transferon™ Batches.

    PubMed

    Medina-Rivero, Emilio; Vallejo-Castillo, Luis; Vázquez-Leyva, Said; Pérez-Sánchez, Gilberto; Favari, Liliana; Velasco-Velázquez, Marco; Estrada-Parra, Sergio; Pavón, Lenin; Pérez-Tapia, Sonia Mayra

    2016-01-01

    Transferon, a biotherapeutic agent that has been used for the past 2 decades for diseases with an inflammatory component, has been approved by regulatory authorities in Mexico (COFEPRIS) for the treatment of patients with herpes infection. The active pharmaceutical ingredient (API) of Transferon is based on polydispersion of peptides that have been extracted from lysed human leukocytes by a dialysis process and a subsequent ultrafiltration step to select molecules below 10 kDa. To physicochemically characterize the drug product, we developed chromatographic methods and an SDS-PAGE approach to analyze the composition and the overall variability of Transferon. Reversed-phase chromatographic profiles of peptide populations demonstrated batch-to-batch consistency from 10 representative batches that harbored 4 primary peaks with a relative standard deviation (RSD) of less than 7%. Aminogram profiles exhibited 17 proteinogenic amino acids and showed that glycine was the most abundant amino acid, with a relative content of approximately 18%. Further, based on their electrophoretic migration, the peptide populations exhibited a molecular mass of about 10 kDa. Finally, we determined the Transferon fingerprint using a mass spectrometry tool. Because each batch was produced from independent pooled buffy coat samples from healthy donors, supplied by a local blood bank, our results support the consistency of the production of Transferon and reveal its peptide identity with regard to its physicochemical attributes. PMID:27525277

  10. NDA BATCH 2002-02

    SciTech Connect

    Lawrence Livermore National Laboratory

    2009-12-09

    QC sample results (daily background checks, 20-gram and 100-gram SGS drum checks) were within acceptable criteria established by WIPP's Quality Assurance Objectives for TRU Waste Characterization. Replicate runs were performed on 5 drums with IDs LL85101099TRU, LL85801147TRU, LL85801109TRU, LL85300999TRU and LL85500979TRU. All replicate measurement results are identical at the 95% confidence level as established by WIPP criteria. Note that the batch covered 5 weeks of SGS measurements from 23-Jan-2002 through 22-Feb-2002. Data packet for SGS Batch 2002-02 generated using gamma spectroscopy with the Pu Facility SGS unit is technically reasonable. All QC samples are in compliance with established control limits. The batch data packet has been reviewed for correctness, completeness, consistency and compliance with WIPP's Quality Assurance Objectives and determined to be acceptable. An Expert Review was performed on the data packet between 28-Feb-02 and 09-Jul-02 to check for potential U-235, Np-237 and Am-241 interferences and address drum cases where specific scan segments showed Se gamma ray transmissions for the 136-keV gamma to be below 0.1 %. Two drums in the batch showed Pu-238 at a relative mass ratio more than 2% of all the Pu isotopes.

  11. Batching System for Superior Service

    NASA Technical Reports Server (NTRS)

    2001-01-01

    Veridian's Portable Batch System (PBS) was the recipient of the 1997 NASA Space Act Award for outstanding software. A batch system is a set of processes for managing queues and jobs. Without a batch system, it is difficult to manage the workload of a computer system. By bundling the enterprise's computing resources, the PBS technology offers users a single coherent interface, resulting in efficient management of the batch services. Users choose which information to package into "containers" for system-wide use. PBS also provides detailed system usage data, a procedure not easily executed without this software. PBS operates on networked, multi-platform UNIX environments. Veridian's new version, PBS Pro,TM has additional features and enhancements, including support for additional operating systems. Veridian distributes the original version of PBS as Open Source software via the PBS website. Customers can register and download the software at no cost. PBS Pro is also available via the web and offers additional features such as increased stability, reliability, and fault tolerance.A company using PBS can expect a significant increase in the effective management of its computing resources. Tangible benefits include increased utilization of costly resources and enhanced understanding of computational requirements and user needs.

  12. Simulated Batch Production of Penicillin

    ERIC Educational Resources Information Center

    Whitaker, A.; Walker, J. D.

    1973-01-01

    Describes a program in applied biology in which the simulation of the production of penicillin in a batch fermentor is used as a teaching technique to give students experience before handling a genuine industrial fermentation process. Details are given for the calculation of minimum production cost. (JR)

  13. Physicochemical Characteristics of Transferon™ Batches

    PubMed Central

    Pérez-Sánchez, Gilberto; Favari, Liliana; Estrada-Parra, Sergio

    2016-01-01

    Transferon, a biotherapeutic agent that has been used for the past 2 decades for diseases with an inflammatory component, has been approved by regulatory authorities in Mexico (COFEPRIS) for the treatment of patients with herpes infection. The active pharmaceutical ingredient (API) of Transferon is based on polydispersion of peptides that have been extracted from lysed human leukocytes by a dialysis process and a subsequent ultrafiltration step to select molecules below 10 kDa. To physicochemically characterize the drug product, we developed chromatographic methods and an SDS-PAGE approach to analyze the composition and the overall variability of Transferon. Reversed-phase chromatographic profiles of peptide populations demonstrated batch-to-batch consistency from 10 representative batches that harbored 4 primary peaks with a relative standard deviation (RSD) of less than 7%. Aminogram profiles exhibited 17 proteinogenic amino acids and showed that glycine was the most abundant amino acid, with a relative content of approximately 18%. Further, based on their electrophoretic migration, the peptide populations exhibited a molecular mass of about 10 kDa. Finally, we determined the Transferon fingerprint using a mass spectrometry tool. Because each batch was produced from independent pooled buffy coat samples from healthy donors, supplied by a local blood bank, our results support the consistency of the production of Transferon and reveal its peptide identity with regard to its physicochemical attributes. PMID:27525277

  14. Microwave assisted thermal treatment of defective coffee beans press cake for the production of adsorbents.

    PubMed

    Franca, Adriana S; Oliveira, Leandro S; Nunes, Anne A; Alves, Cibele C O

    2010-02-01

    Defective coffee press cake, a residue from coffee oil biodiesel production, was evaluated as an adsorbent for removal of basic dyes (methylene blue--MB) from aqueous solutions. The adsorbent was prepared by microwave treatment, providing a significant reduction in processing time coupled to an increase in adsorption capacity in comparison to conventional carbonization in a muffle furnace. Batch adsorption tests were performed at 25 degrees C and the effects of particle size, contact time, adsorbent dosage and initial solution pH were investigated. Adsorption kinetics was better described by a second-order model. The experimental adsorption equilibrium data were fitted to Langmuir, Freundlich and Tempkin adsorption models, with Langmuir providing the best fit. The results presented in this study show that microwave activation presents great potential as an alternative method in the production of adsorbents. PMID:19767204

  15. Enhanced removal of sulfonamide antibiotics by KOH-activated anthracite coal: Batch and fixed-bed studies.

    PubMed

    Zuo, Linzi; Ai, Jing; Fu, Heyun; Chen, Wei; Zheng, Shourong; Xu, Zhaoyi; Zhu, Dongqiang

    2016-04-01

    The presence of sulfonamide antibiotics in aquatic environments poses potential risks to human health and ecosystems. In the present study, a highly porous activated carbon was prepared by KOH activation of an anthracite coal (Anth-KOH), and its adsorption properties toward two sulfonamides (sulfamethoxazole and sulfapyridine) and three smaller-sized monoaromatics (phenol, 4-nitrophenol and 1,3-dinitrobenzene) were examined in both batch and fixed-bed adsorption experiments to probe the interplay between adsorbate molecular size and adsorbent pore structure. A commercial powder microporous activated carbon (PAC) and a commercial mesoporous carbon (CMK-3) possessing distinct pore properties were included as comparative adsorbents. Among the three adsorbents Anth-KOH exhibited the largest adsorption capacities for all test adsorbates (especially the two sulfonamides) in both batch mode and fixed-bed mode. After being normalized by the adsorbent surface area, the batch adsorption isotherms of sulfonamides on PAC and Anth-KOH were displaced upward relative to the isotherms on CMK-3, likely due to the micropore-filling effect facilitated by the microporosity of adsorbents. In the fixed-bed mode, the surface area-normalized adsorption capacities of Anth-KOH for sulfonamides were close to that of CMK-3, and higher than that of PAC. The irregular, closed micropores of PAC might impede the diffusion of the relatively large-sized sulfonamide molecules and in turn led to lowered fixed-bed adsorption capacities. The overall superior adsorption of sulfonamides on Anth-KOH can be attributed to its large specific surface area (2514 m(2)/g), high pore volume (1.23 cm(3)/g) and large micropore sizes (centered at 2.0 nm). These findings imply that KOH-activated anthracite coal is a promising adsorbent for the removal of sulfonamide antibiotics from aqueous solution. PMID:26802515

  16. Adsorption of high ammonium nitrogen from wastewater using a novel ceramic adsorbent and the evaluation of the ammonium-adsorbed-ceramic as fertilizer.

    PubMed

    Zhao, Yingxin; Yang, Yingnan; Yang, Shengjiong; Wang, Qinghong; Feng, Chuanping; Zhang, Zhenya

    2013-03-01

    A novel ceramic adsorbent was developed to adsorb ammonium from high concentration ammonium contaminated wastewater. Typical gardening cultivation mediums in Japan-Kanuma clay and Akadama clay were used to synthesize the ceramic adsorbent. Static batch experiments were conducted to investigate the effect of various parameters such as contact time, initial ammonium concentration, adsorbent dosage, and competing cations during the ammonium adsorption process. The results revealed that the Freundlich isotherm model fitted better with the adsorption process than the Langmuir model, and the adsorption process was well described by pseudo-second-order kinetic model. The maximum nitrogen adsorption capacity of the ceramic adsorbent was 75.5 mg g(-1) at an initial NH(4)(+)-N concentration of 10,000 mg L(-1), dosage of 20 g L(-1), and contact time of 480 min. Results demonstrated that the low-cost ceramic adsorbent directly used as nitrogen fertilizer was feasible for its high ammonium nitrogen content, nontoxic effect on the environment and excellent soil properties. PMID:23153680

  17. M4FT-15OR03100415 - Update on COF-based Adsorbent Survey

    SciTech Connect

    Mayes, Richard T.; Dai, Sheng

    2015-02-01

    This letter report provides an update on activities focused on generating nanoporous adsorbents involving covalent organic frameworks (COF) and zeolitic imidazolium frameworks (ZIF). The adsorbents have been generated and screened in a uranyl-spiked brine (6 ppm U) to understand uranyl-binding behavior. Porous organic polymers (POP) also qualify under this title and are similar to the COF PPN-6 that is discussed herein. Seven COF/POP and one 1 ZIF were synthesized and screened for uranyl adsorption. Seawater screening is on-going via batch testing while flow screening systems are being developed at PNNL.

  18. NDA Batch 2002-13

    SciTech Connect

    Hollister, R

    2009-09-17

    QC sample results (daily background check drum and 100-gram SGS check drum) were within acceptance criteria established by WIPP's Quality Assurance Objectives for TRU Waste Characterization. Replicate runs were performed on drum LL85501243TRU. Replicate measurement results are identical at the 95% confidence level as established by WIPP criteria. HWM NCAR No. 02-1000168 issued on 17-Oct-2002 regarding a partially dislodged Cd sheet filter on the HPGe coaxial detector. This physical geometry occurred on 01-Oct-2002 and was not corrected until 10-Oct-2002, during which period is inclusive of the present batch run of drums. Per discussions among the Independent Technical Reviewer, Expert Reviewer and the Technical QA Supervisor, as well as in consultation with John Fleissner, Technical Point of Contact from Canberra, the analytical results are technically reliable. All QC standard runs during this period were in control. Data packet for SGS Batch 2002-13 generated using passive gamma-ray spectroscopy with the Pu Facility SGS unit is technically reasonable. All QC samples are in compliance with establiShed control limits. The batch data packet has been reviewed for correctness, completeness, consistency and compliance with WIPP's Quality Assurance Objectives and determined to be acceptable.

  19. Conformational changes of adsorbed proteins

    NASA Astrophysics Data System (ADS)

    Allen, Scott

    2005-03-01

    The adsorption of bovine serum albumin (BSA) and pepsin to gold surfaces has been studied using surface plasmon resonance (SPR). Proteins are adsorbed from solution onto a gold surface and changes in the conformation of the adsorbed proteins are induced by changing the buffer solution. We selected pH and ionic strength values for the buffer solutions that are known from our circular dichroism measurements to cause conformational changes of the proteins in bulk solution. We find that for both BSA and pepsin the changes in conformation are impeded by the interaction of the protein with the gold surface.

  20. Removal of arsenic from water using the adsorbent: New Zealand iron-sand.

    PubMed

    Panthi, Sudan Raj; Wareham, David Geraint

    2011-01-01

    Adsorption is a technology used to remove arsenic from water contaminated at levels above drinking water standards. In this study, New Zealand Iron-Sand (NZIS), a naturally-available adsorbent was investigated for its efficiency in removing both As (III) and As (V). Several batch tests were conducted with different concentrations of arsenic at different pH conditions. During the batch tests, the maximum adsorption of As (III) occurred at a pH of 7.5, while As (V) adsorption reached its maximum value at a pH of 3. Both Langmuir and Freundlich adsorption models were found to fit with R(2) values greater than 0.92. From the Langmuir adsorption model, the maximum adsorption capacity of NZIS for As (III) and As (V) were estimated to be 1,250 and 500 μg/g, respectively. These values were substantial enough to consider NZIS a promising new adsorbent for arsenic removal. PMID:21991930

  1. Low-cost magnetic adsorbent for As(III) removal from water: adsorption kinetics and isotherms.

    PubMed

    Kango, Sarita; Kumar, Rajesh

    2016-01-01

    Magnetite nanoparticles as adsorbent for arsenic (As) were coated on sand particles. The coated sand was used for the removal of highly toxic element 'As(III)' from drinking water. Here, batch experiments were performed with the variation of solution pH, adsorbent dose, contact time and initial arsenic concentration. The adsorbent showed significant removal efficiency around 99.6 % for As(III). Analysis of adsorption kinetics revealed that the adsorbent follows pseudo-second-order kinetics model showing R (2) = 0.999, whereas for pseudo-first-order kinetics model, the value of R (2) was 0.978. In the case of adsorption equilibrium, the data is well fitted with Langmuir adsorption isotherm model (R (2) > 0.99), indicating monolayer adsorption of As(III) on the surface of adsorbent. The existence of commonly present ions in water influences the removal efficiency of As(III) minutely in the following order PO4 (3-) > HCO3 (-) > Cl(-) > SO4 (2-). The obtained adsorbent can be used to overcome the problem of water filtration in rural areas. Moreover, as the nano-magnetite is coated on the sand, it avoids the problem of extraction of nanoparticles from treated water and can easily be removed by a simple filtration process. PMID:26711813

  2. 2-chlorophenol sorption from aqueous solution using granular activated carbon and polymeric adsorbents

    NASA Astrophysics Data System (ADS)

    Ghatbandhe, A. S.; Jahagirdar, H. G.; Yenkie, M. K. N.; Deosarkar, S. D.

    2013-08-01

    Adsorption equilibrium and kinetics of 2-chlorophenol (2-CP) one of the chlorophenols (CPs) onto bituminous coal based Filtrasorb-400 grade granular activated carbon and three different types of polymeric adsorbents were studied in aqueous solution in a batch system. Langmuir isotherm models were applied to experimental equilibrium data of 2-CP adsorption. Equilibrium data fitted very well to the Langmuir equilibrium models of 2-CP. Adsorbent monolayer capacity Q Langmuir constant b and adsorption rate constants k a were evaluated. 2-CP adsorption using GAC is very rapid in the first hour of contact where 70-80% of the adsorbate is removed by GAC followed by a slow approach to equilibrium. Whereas in case of polymeric adsorbents 60-65% of the adsorbate is removed in the first 30 min which is then followed by a slow approach to equilibrium. The order of adsorption of 2-CP on different adsorbents used in the study is found to be in following order: F-400 > XAD-1180 > XAD-4 > XAD-7HP.

  3. Natural Iraqi palygorskite clay as low cost adsorbent for the treatment of dye containing industrial wastewater.

    PubMed

    Nassir Taha, Dakhil; Sadi Samaka, Isra'a

    2012-01-01

    In this study, natural Iraqi low- cost locally available clay (palygorskite) was studied for its potential use as an adsorbent for removal Congo red from aqueous solutions. Batch type experiments were conducted to study the effect of contact time, initial pH of the dye solution, initial dye concentration, adsorbent dosage, and particle size of adsorbent on adsorption capacity of Congo red. The adsorption occurred very fast initially and attains equilibrium within 60 min. When the effect of pH of solution dye on the yield adsorption has been carried in a range of 2-10, the adsorption obtained was nearly the same with very slightly effect of pH and it was reported that above 49.07 mg/g of Cong red by palygorskite clay occurred in the pH range 2 to 10. It was observed that the removal of Congo red increase with increasing initial dye concentration and adsorbent dose, but, adsorption capacity decrease with increasing adsorbent dose. The adsorption capacity increase with decreasing particle size of adsorbent. The equilibrium adsorption data were interpreted using Langmuir and Freundlich isotherm models. The obtained results revealed that the equilibrium data closely followed both models, but the Langmuir isotherm fitted the data better. The maximum adsorption capacity was found to be 99 mg/g at ambient temperature. Results indicate that Iraqi palygorskite clay could be employed as a low cost alternative to commercial activated carbon in wastewater treatment for the removal of colour and dyes. PMID:23196874

  4. Novel adsorbent applicability for decontamination of printing wastewater

    NASA Astrophysics Data System (ADS)

    Kiurski, Jelena; Oros, Ivana; Ranogajec, Jonjaua; Kecic, Vesna

    2013-04-01

    (up to 93.5%) to remove Zn(II) ion from printing wastewaters. The results showed that fired clay, fired clay modified with polymer addition, natural zeolite and bentonite can be used for Zn(II) ion removal from printing wastewaters by adsorption method in laboratory batch mode. Based on higher affinity to the Zn(II) ion adsorption than fired clay, bentonite and zeolite it was concluded that feasibility of newly designed clayey adsorbent, fired clay with 5 mass% PEG addition is very good. A new designed clayey adsorbent is an effective and economical alternative for the Zn(II) ion removal from printing wastewaters. Acknowledgment: The authors acknowledge the financial support of the Ministry of Education, Science and Technological Development of the Republic of Serbia (Projects No. TR 34014, III 45008 and III 46009).

  5. Supercritical fluid regeneration of adsorbents

    NASA Astrophysics Data System (ADS)

    Defilippi, R. P.; Robey, R. J.

    1983-05-01

    The results of a program to perform studies supercritical (fluid) carbon dioxide (SCF CO2) regeneration of adsorbents, using samples of industrial wastewaters from manufacturing pesticides and synthetic solution, and to estimate the economics of the specific wastewater treatment regenerations, based on test data are given. Processing costs for regenerating granular activated carbon GAC) for treating industrial wastewaters depend on stream properties and regeneration throughput.

  6. From MDF and PB wastes to adsorbents for the removal of pollutants

    NASA Astrophysics Data System (ADS)

    Gomes, J. A. F. L.; Azaruja, B. A.; Mourão, P. A. M.

    2016-09-01

    The production of activated carbons in powder and monolith forms, by physical activation with CO2, with specific surface areas between 804 and 1469 m2 g-1, porous volume between 0.33 and 0.59 cm3 g-1, with basic nature (PZC ∼ 9.6-10.6) was achieved in our lab, from medium density fibreboard (MDF) and particleboard (PB), engineered wood composites wastes. These highly porous adsorbents were applied in kinetic and equilibrium adsorption studies, in batch and dynamic modes, in powder and monolith forms, of specific adsorptives, considered pollutants, namely phenol (P), p-nitrophenol (PNP) and neutral red (NR). In batch the maximum adsorbed amount was 267, 162 and 92 mg g-1, for PNP, P and NR, respectively. The application of different kinetic models (pseudo-first order, pseudo-second order and intraparticle diffusion model) leads to a better knowledge of the adsorption mechanisms of those adsorptives. The results obtained in the kinetic and equilibrium tests show that the combination of the structural features and the surface chemistry nature of the adsorbents, with the adsorptives properties, establish the kinetic performance, the type and amount adsorbed for each system. This work confirms the potential of these types of wastes in the production of activated carbons and its application in adsorption from liquid phase.

  7. Adsorption of phenolic compounds from aqueous solutions using carbon nanoporous adsorbent coated with polymer

    NASA Astrophysics Data System (ADS)

    Anbia, Mansoor; Ghaffari, Arezoo

    2009-09-01

    Phenolic compounds are a widespread class of water pollutants that are known to cause serious human health problems; and the demand for effective adsorbents for the removal of toxic compounds is increasing. In this work adsorption of phenol, resorcinol and p-cresol on mesoporous carbon material (CMK-1) and modified with polyaniline polymer (CMK-1/PANI) has been investigated in attempt to explore the possibility of using nanoporous carbon as an efficient adsorbent for pollutants. It was found that CMK-1/PANI exhibits significant adsorption for phenolic derivatives. Batch adsorption studies were carried out to study the effect of various parameters like adsorbent dose, pH, initial concentration and contact time. From the sorption studies it was observed that the uptake of resorcinol was higher than other phenolic derivatives. Freundlich and Langmuir adsorption isotherms were used to model the equilibrium adsorption data for phenolic compounds.

  8. Preparation of metal adsorbent from poly(methyl acrylate)-grafted-cassava starch via gamma irradiation

    NASA Astrophysics Data System (ADS)

    Suwanmala, Phiriyatorn; Hemvichian, Kasinee; Hoshina, Hiroyuki; Srinuttrakul, Wannee; Seko, Noriaki

    2012-08-01

    Metal adsorbent containing hydroxamic acid groups was successfully synthesized by radiation-induced graft copolymerization of methyl acrylate (MA) onto cassava starch. The optimum conditions for grafting were studied in terms of % degree of grafting (Dg). Conversion of the ester groups present in poly(methyl acrylate)-grafted-cassava starch copolymer into hydroxamic acid was carried out by treatment with hydroxylamine (HA) in the presence of alkaline solution. The maximum percentage conversion of the ester groups of the grafted copolymer, % Dg=191 (7.63 mmol/g of MA), into the hydroxamic groups was 70% (5.35 mmol/g of MA) at the optimum condition. The adsorbent of 191%Dg had total adsorption capacities of 2.6, 1.46, 1.36, 1.15 and 1.6 mmol/g-adsorbent for Cd2+, Al3+, UO22+, V5+ and Pb2+, respectively, in the batch mode adsorption.

  9. The painkiller for batch control headaches

    SciTech Connect

    Haxthausen, N.

    1995-10-01

    The world of batch control is a complicated one, containing many of the issues common to continuous processes, as well as such concerns as complex sequential control, product variation, dynamic scheduling and lot tracking. Many different and poorly structured approaches have been taken to these problems, and communication between vendors and users has been troublesome. The newly defined ISA standard, ``SP88, Part 1: Batch Control Terminology,`` brings a large degree of order to the batch control process. SP88 provides definitions of many of the common elements of batch process equipment and recipe steps. In addition, it provides a methodology for logically arranging batch process control, so that the process is understandable and, most importantly, verifiable. Part 1 of this article introduces the important terms and concepts of SP88 along with recommendations for their implementation. In Part 2, a method is proposed to streamline the process of designing and constructing batch manufacturing facilities.

  10. Adding coal dust to coal batch

    SciTech Connect

    V.S. Shved; A.V.Berezin

    2009-05-15

    The granulometric composition of coke dust from the dry-slaking machine is determined. The influence of additions of 3-7% coke dust on the quality of industrial coking batch and the coke obtained by box coking is estimated. Adding 1% coke dust to coking batch does not markedly change the coke quality. Industrial equipment for the supply of dry-slaking dust to the batch is described.

  11. Plutonium immobilization feed batching system concept report

    SciTech Connect

    Erickson, S.

    2000-07-19

    The Plutonium Immobilization Facility will encapsulate plutonium in ceramic pucks and seal the pucks inside welded cans. Remote equipment will place these cans in magazines and the magazines in a Defense Waste Processing Facility (DWPF) canister. The DWPF will fill the canister with high level waste glass for permanent storage. Feed batching is one of the first process steps involved with first stage plutonium immobilization. It will blend plutonium oxide powder before it is combined with other materials to make pucks. This report discusses the Plutonium Immobilization feed batching process preliminary concept, batch splitting concepts, and includes a process block diagram, concept descriptions, a preliminary equipment list, and feed batching development areas.

  12. Method And Apparatus For Regenerating Nox Adsorbers

    DOEpatents

    Driscoll, J. Joshua; Endicott, Dennis L.; Faulkner, Stephen A.; Verkiel, Maarten

    2006-03-28

    Methods and apparatuses for regenerating a NOx adsorber coupled with an exhaust of an engine. An actuator drives a throttle valve to a first position when regeneration of the NOx adsorber is desired. The first position is a position that causes the regeneration of the NOx adsorber. An actuator drives the throttle valve to a second position while regeneration of the NOx adsorber is still desired. The second position being a position that is more open than the first position and operable to regenerate a NOx adsorber.

  13. Development of high efficiency silica coated β-cyclodextrin polymeric adsorbent for the removal of emerging contaminants of concern from water.

    PubMed

    Bhattarai, Bikash; Muruganandham, M; Suri, Rominder P S

    2014-05-30

    This article reports the removal of several emerging contaminants (ECs) from water using novel adsorbent comprising of β-cyclodextrin (β-CD) coated on silica. Fourteen different adsorbents were synthesized under different experimental conditions using two different crosslinking agents (hexamethylene diisocyanate (HMDI) and epichlorohydrin (EPI)) and co-polymers (glycidoxypropyl trimethoxysilane (GPTS) and aminopropyl triethoxysilane (APTES). The adsorption capacities of the synthesized adsorbents were initially evaluated using 17β-estradiol, perfluorooctanoic acid (PFOA), and bisphenol-A (BPA) as adsorbates. The adsorbent prepared by using HMDI as crosslinking agent with DMSO as solvent was observed to perform the best, and removed more than 90% of 17β-estradiol, PFOA, and BPA. Furthermore, the β-CD loading on the ECs removal was studied which showed that the adsorbate removal increases with increase in loading of β-CD on the substrate. The best adsorbent was resynthesized in seven batches and its performance was reproducible for the removal of ten steroid hormones. The adsorbent showed very good regeneration potential for four successive adsorption-regeneration cycles to remove steroid hormones and PFOA. A plausible mechanism of adsorption is proposed. The synthesized best adsorbent is characterized using FTIR, HR-TEM, TGA and nitrogen adsorption analysis. The TGA results showed that the adsorbent has thermal stability of upto 300°C. PMID:24727017

  14. Method and apparatus for melting glass batch

    DOEpatents

    Fassbender, Alexander G.; Walkup, Paul C.; Mudge, Lyle K.

    1988-01-01

    A glass melting system involving preheating, precalcining, and prefluxing of batch materials prior to injection into a glass furnace. The precursors are heated by convection rather than by radiation in present furnaces. Upon injection into the furnace, batch materials are intimately coated with molten flux so as to undergo or at least begin the process of dissolution reaction prior to entering the melt pool.

  15. Computer Batch Files Shorten Many Complicated Procedures.

    ERIC Educational Resources Information Center

    Deppa, Joan

    1987-01-01

    Defines "batch files," claiming that they can shorten many complicated computer procedures. Describes how batch file was created using the computer program "PC-Write" to streamline the process of creating a work disk and increase students' computer literacy. Lists and discusses each element in the file. Provides references for more information.…

  16. Adsorption of copper cyanide on chemically active adsorbents

    SciTech Connect

    Lee, J.S.; Deorkar, N.V.; Tavlarides, L.L.

    1998-07-01

    An inorganic chemically active adsorbent (ICAA), SG(1)-TEPA (tetraethylenepentaamine)-propyl, is developed for removal, recovery, and recycling of copper cyanide from industrial waste streams. Equilibrium studies are executed to determine and model adsorption of the copper cyanide complex from aqueous solutions in a batch and packed column. It appears that adsorption is dependent on anionic copper cyanide species and the basicity of the ligand. Aqueous-phase equilibrium modeling shows that monovalent (Cu(CN){sub 2}{sup {minus}}), divalent (Cu(CN){sub 3}{sup 2{minus}}), and trivalent (Cu(CN){sub 4}{sup 3{minus}}) species of copper cyanide exist in the solution, depending on the pH and the concentration of total cyanide ions. Batch adsorption data are modeled using a modified multicomponent Langmuir isotherm which includes aqueous-phase speciation and basicity of the SG(1)-TEPA-propyl. This developed model is applied with a mass balance equation to describe the adsorption of copper cyanide complexes in a packed column.

  17. Activated carbon adsorbents from waste tires for air quality control

    SciTech Connect

    Lehmann, C.M.B.; Rostam-Abadi, M.; Rood, M.J.; Hsi, H.C.

    1999-07-01

    This study evaluates methodologies for utilizing waste tire rubber to produce carbonaceous adsorbents for use in air quality control operations. Such an approach provides a two-fold environmental and economic benefit. A recycling path is developed for waste tire rubber and new adsorbents are produced from a low cost feedstock for use in environmentally-related operations. Bench-scale and pilot-scale quantities of tire-derived activated carbon (TDAC) were produced from waste tire rubber. Raw tire rubber samples and devolatilized tire char were obtained from several US vendors. The raw samples were analyzed using proximate, ultimate, and elemental analyses. Batches of activated carbon samples were prepared using a bench-scale fixed-tubular reactor to prepare {approximately}10 g samples and a fluidized-bed reactor to prepare {approximately}100 g quantities. About 25 kg of activated carbon was also produced at a pilot-scale commercial facility. The resulting TDACs were then characterized by nitrogen adsorption at 77K. The sample surface areas were determined by the BET method, and the pore size distribution (PSD) was evaluated using the BJH model, and a 3-D PSD model. Performance of the TDACs was evaluated in their ability to remove gaseous mercury species from simulated power-plant flue-gas streams, and for the removal of organic compounds (e.g., acetone and 1,1,1-trichloroethane) from flowing gas streams.

  18. Batch Scheduling a Fresh Approach

    NASA Technical Reports Server (NTRS)

    Cardo, Nicholas P.; Woodrow, Thomas (Technical Monitor)

    1994-01-01

    The Network Queueing System (NQS) was designed to schedule jobs based on limits within queues. As systems obtain more memory, the number of queues increased to take advantage of the added memory resource. The problem now becomes too many queues. Having a large number of queues provides users with the capability to gain an unfair advantage over other users by tailoring their job to fit in an empty queue. Additionally, the large number of queues becomes confusing to the user community. The High Speed Processors group at the Numerical Aerodynamics Simulation (NAS) Facility at NASA Ames Research Center developed a new approach to batch job scheduling. This new method reduces the number of queues required by eliminating the need for queues based on resource limits. The scheduler examines each request for necessary resources before initiating the job. Also additional user limits at the complex level were added to provide a fairness to all users. Additional tools which include user job reordering are under development to work with the new scheduler. This paper discusses the objectives, design and implementation results of this new scheduler

  19. Defluoridation of groundwater using brick powder as an adsorbent.

    PubMed

    Yadav, Asheesh Kumar; Kaushik, C P; Haritash, Anil Kumar; Kansal, Ankur; Rani, Neetu

    2006-02-01

    Defluoridation of groundwater using brick powder as an adsorbent was studied in batch process. Different parameters of adsorption, viz. effect of pH, effect of dose and contact time were selected and optimized for the study. Feasible optimum conditions were applied to two groundwater samples of high fluoride concentration to study the suitability of adsorbent in field conditions. Comparison of adsorption by brick powder was made with adsorption by commercially available activated charcoal. In the optimum condition of pH and dose of adsorbents, the percentage defluoridation from synthetic sample, increased from 29.8 to 54.4% for brick powder and from 47.6 to 80.4% for commercially available activated charcoal with increasing the contact time starting from 15 to 120 min. Fluoride removal was found to be 48.73 and 56.4% from groundwater samples having 3.14 and 1.21 mg l(-1) fluoride, respectively, under the optimized conditions. Presence of other ions in samples did not significantly affect the deflouridation efficiency of brick powder. The optimum pH range for brick powder was found to be 6.0-8.0 and adsorption equilibrium was found to be 60 min. These conditions make it very suitable for use in drinking water treatment. Deflouridation capacity of brick powder can be explained on the basis of the chemical interaction of fluoride with the metal oxides under suitable pH conditions. The adsorption process was found to follow first order rate mechanism as well as Freundlich isotherm. PMID:16233952

  20. 27 CFR 19.748 - Dump/batch records.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Dump/batch records. 19.748.../batch records. (a) Format of dump/batch records. Proprietor's dump/batch records shall contain, as... ingredients used; (10) Formula number; (11) Quantity of ingredients used in the batch that have...

  1. Investigation on removal of malachite green using EM based compost as adsorbent.

    PubMed

    Bhagavathi Pushpa, T; Vijayaraghavan, J; Sardhar Basha, S J; Sekaran, V; Vijayaraghavan, K; Jegan, J

    2015-08-01

    The discarded materials from different sources can be utilized as effective materials in wastewater remediation. This proposed study was aimed mainly to investigate the possibility of Effective Microorganisms based compost (EMKC), which is derived from the kitchen solid waste, as a non-conventional low cost adsorbent for the removal of malachite green from aqueous solution. Batch experiments were carried out to evaluate the optimum operating parameters like pH (2-9), initial dye concentration (50-1000mg/L), adsorbent particle size (0.6-2.36mm) and adsorbent dosage (2-12g/L). EMKC recorded maximum uptake of 136.6mg/g of MG at pH 8, initial dye concentration 1000mg/L, adsorbent particle size 1.18mm and adsorbent dosage 4g/L. Two and three parameter adsorption models were employed to describe experimental biosorption isotherm data. The results revealed that the Sips model resulted in better fit than other models. The pseudo-first and -second order models were applied to describe kinetic data, of which the pseudo-second order described experimental data better with high correlation coefficient. This investigation suggested that EMKC could be an effective and low cost material for the removal of malachite green dye from aqueous solution. PMID:25938698

  2. Esterified coir pith as an adsorbent for the removal of Co(II) from aqueous solution.

    PubMed

    Parab, Harshala; Joshi, Shreeram; Shenoy, Niyoti; Lali, Arvind; Sarma, U S; Sudersanan, M

    2008-04-01

    Coir pith was chemically modified for the adsorption of cobalt(II) ions from aqueous solution. Chemical modification was done by esterification using succinic anhydride followed by activation with NaHCO(3) in order to improve the adsorption of Co(II). Adsorptive removal of Co(II) from aqueous solution onto modified coir pith was evaluated in batch studies under varying conditions of agitation time and metal ion concentration to assess the kinetic and equilibrium parameters. A pseudo-second-order kinetic model fitted well for the sorption of Co(II) onto modified coir pith. Sorption kinetics showed that the loading of Co(II) by this material was quite fast under ambient conditions. The Langmuir and Freundlich equilibrium isotherm models provided excellent fits for the adsorption data, with R(2) of 0.99 and 0.98, respectively. After esterification, the maximum Co(II) sorption loading Q(0); was greatly improved. It is evident that chemically modified adsorbent exhibits better Co(II) removal capability than raw adsorbent suggesting that surface modification of the adsorbent generates more adsorption sites on its solid surface for metal adsorption. A complete recovery of the adsorbed metal ions from the spent adsorbent was achieved by using 1.0N HCl. PMID:17611104

  3. Visualization and Measurement of Adsorption/Desorption Process of Ethanol in Activated Carbon Adsorber

    NASA Astrophysics Data System (ADS)

    Asano, Hitoshi; Murata, Kenta; Takenaka, Nobuyuki; Saito, Yasushi

    Adsorption refrigerator is one of the efficient tools for waste heat recovery, because the system is driven by heat at relative low temperature. However, the coefficient of performance is low due to its batch operation and the heat capacity of the adsorber. In order to improve the performance, it is important to optimize the configuration to minimize the amount of driving heat, and to clarify adsorption/desorption phenomena in transient conditions. Neutron radiography was applied to visualize and measure the adsorption amount distribution in an adsorber. The visualization experiments had been performed at the neutron radiography facility of E-2 port of Kyoto University Research Reactor. Activated carbon and ethanol were used as the adsorbent and refrigerant. From the acquired radiographs, adsorption amount was quantitatively measured by applying the umbra method using a checkered neutron absorber with boron powder. Then, transient adsorption and desorption processes of a rectangular adsorber with 84 mm in width, 50 mm in height and 20 mm in depth were visualized. As the result, the effect of fins in the adsorbent layer on the adsorption amount distribution was clearly visualized.

  4. Enhanced removal of nitrate from water using surface modification of adsorbents--a review.

    PubMed

    Loganathan, Paripurnanda; Vigneswaran, Saravanamuthu; Kandasamy, Jaya

    2013-12-15

    Elevated concentration of nitrate results in eutrophication of natural water bodies affecting the aquatic environment and reduces the quality of drinking water. This in turn causes harm to people's health, especially that of infants and livestock. Adsorbents with the high capacity to selectively adsorb nitrate are required to effectively remove nitrate from water. Surface modifications of adsorbents have been reported to enhance their adsorption of nitrate. The major techniques of surface modification are: protonation, impregnation of metals and metal oxides, grafting of amine groups, organic compounds including surfactant coating of aluminosilicate minerals, and heat treatment. This paper reviews current information on these techniques, compares the enhanced nitrate adsorption capacities achieved by the modifications, and the mechanisms of adsorption, and presents advantages and drawbacks of the techniques. Most studies on this subject have been conducted in batch experiments. These studies need to include continuous mode column trials which have more relevance to real operating systems and pilot-plant trials. Reusability of adsorbents is important for economic reasons and practical treatment applications. However, only limited information is available on the regeneration of surface modified adsorbents. PMID:24211565

  5. Removal of lead and zinc ions from water by low cost adsorbents.

    PubMed

    Mishra, P C; Patel, R K

    2009-08-30

    In this study, activated carbon, kaolin, bentonite, blast furnace slag and fly ash were used as adsorbent with a particle size between 100 mesh and 200 mesh to remove the lead and zinc ions from water. The concentration of the solutions prepared was in the range of 50-100 mg/L for lead and zinc for single and binary systems which are diluted as required for batch experiments. The effect of contact time, pH and adsorbent dosage on removal of lead and zinc by adsorption was investigated. The equilibrium time was found to be 30 min for activated carbon and 3h for kaolin, bentonite, blast furnace slag and fly ash. The most effective pH value for lead and zinc removal was 6 for activated carbon. pH value did not effect lead and zinc removal significantly for other adsorbents. Adsorbent doses were varied from 5 g/L to 20 g/L for both lead and zinc solutions. An increase in adsorbent doses increases the percent removal of lead and zinc. A series of isotherm studies was undertaken and the data evaluated for compliance was found to match with the Langmuir and Freundlich isotherm models. To investigate the adsorption mechanism, the kinetic models were tested, and it follows second order kinetics. Kinetic studies reveals that blast furnace slag was not effective for lead and zinc removal. The bentonite and fly ash were effective for lead and zinc removal. PMID:19299083

  6. The application of textile sludge adsorbents for the removal of Reactive Red 2 dye.

    PubMed

    Sonai, Gabriela G; de Souza, Selene M A Guelli U; de Oliveira, Débora; de Souza, Antônio Augusto U

    2016-03-01

    Sludge from the textile industry was used as a low-cost adsorbent to remove the dye Reactive Red 2 from an aqueous solution. Adsorbents were prepared through the thermal and chemical treatment of sludge originating from physical-chemical (PC) and biological (BIO) effluent treatment processes. The adsorbent characterization was carried out through physical-chemical analysis, X-ray fluorescence (XRF) spectroscopy, Fourier transform infrared (FTIR) spectroscopy, pHPZC determination, Boehm titration method, Brunauer-Emmett-Teller (BET) surface area analysis and scanning electron microscopy (SEM). Batch kinetic experiments and adsorption isotherm modeling were conducted under different pH and temperature conditions. The results for the kinetic studies indicate that the adsorption processes associated with these systems can be described by a pseudo-second-order model and for the equilibrium data the Langmuir model provided the best fit. The adsorption was strongly dependent on the pH but not on the temperature within the ranges studied. The maxima adsorption capacities were 159.3 mg g(-1) for the BIO adsorbent and 213.9 mg g(-1) for PC adsorbent at pH of 2 and 25 °C. PMID:26706227

  7. γ-Cyclodextrin-polyurethane copolymer adsorbent for selective removal of endotoxin from DNA solution.

    PubMed

    Sakata, Masayo; Uezono, Koji; Kimura, Kasane; Todokoro, Masami

    2013-12-01

    Copolymer particles for removal of endotoxins (lipopolysaccharides, LPSs) were prepared by suspension copolymerization of γ-cyclodextrin (CyD) and 1,6-hexamethylenediisocyanate. The LPS-removing activity of the copolymer particles was compared with that of poly(ε-lysine)-immobilized Cellufine (cationic adsorbent) or polystyrene particles (hydrophobic adsorbent) by a batch method. When DNA was present in solution with LPSs under physiological conditions (pH 6.0, ionic strength of μ = 0.05-0.8), LPS-removing activity of the cationic or hydrophobic adsorbent was unsatisfactory because both the DNA and the LPSs were adsorbed onto each adsorbent. By contrast, the copolymer particles with γ-CyD cavity (CyD content: 14-20 mol%) could selectively remove LPSs from a DNA solution (50 μg ml(-1), pH 6.0, and μ = 0.05-0.2) containing LPSs (15 EU ml(-1)) without the adsorption of DNA. The residual concentration of LPSs in the treated DNA solution was below 0.1 EU ml(-1), and the recovery of DNA was 99%. PMID:23969015

  8. Thermal Analysis of Waste Glass Batches: Effect of Batch Makeup on Gas-Evolving Reactions

    SciTech Connect

    Pierce, David A.; Hrma, Pavel R.; Marcial, Jose

    2013-01-21

    Batches made with a variety of precursors were subjected to thermo-gravimetric analysis. The baseline modifications included all-nitrate batch with sucrose addition, all-carbonate batch, and batches with different sources of alumina. All batches were formulated for a single glass composition (a vitrified simulated high-alumina high-level waste). Batch samples were heated from the ambient temperature to 1200°C at constant heating rates ranging from 1 K/min to 50 K/min. Major gas evolving reactions began at temperatures just above 100°C and were virtually complete by 650°C. Activation energies for major reactions were obtained with the Kissinger’s method. A rough model for the overall kinetics of the batch-conversion was developed to be eventually applied to a mathematical model of the cold cap.

  9. A novel fiber-based adsorbent technology

    SciTech Connect

    Reynolds, T.A.

    1997-10-01

    In this Phase I Small Business Innovation Research program, Chemica Technologies, Inc. is developing an economical, robust, fiber-based adsorbent technology for removal of heavy metals from contaminated water. The key innovation is the development of regenerable adsorbent fibers and adsorbent fiber cloths that have high capacity and selectivity for heavy metals and are chemically robust. The process has the potential for widespread use at DOE facilities, mining operations, and the chemical process industry.

  10. Quasiparticle excitations of adsorbates on doped graphene

    NASA Astrophysics Data System (ADS)

    Lischner, Johannes; Wickenburg, Sebastian; Wong, Dillon; Karrasch, Christoph; Wang, Yang; Lu, Jiong; Omrani, Arash A.; Brar, Victor; Tsai, Hsin-Zon; Wu, Qiong; Corsetti, Fabiano; Mostofi, Arash; Kawakami, Roland K.; Moore, Joel; Zettl, Alex; Louie, Steven G.; Crommie, Mike

    Adsorbed atoms and molecules can modify the electronic structure of graphene, but in turn it is also possible to control the properties of adsorbates via the graphene substrate. In my talk, I will discuss the electronic structure of F4-TCNQ molecules on doped graphene and present a first-principles based theory of quasiparticle excitations that captures the interplay of doping-dependent image charge interactions between substrate and adsorbate and electron-electron interaction effects on the molecule. The resulting doping-dependent quasiparticle energies will be compared to experimental scanning tunnelling spectra. Finally, I will also discuss the effects of charged adsorbates on the electronic structure of doped graphene.

  11. Batch gravitational sedimentation of slurries.

    PubMed

    Chu, C P; Ju, S P; Lee, D J; Mohanty, K K

    2002-01-01

    We investigated the batch settling behavior of the kaolin slurry and the UK ball clay slurry at various initial solids fractions (phi(0)s) using a computerized axial tomography scanner (CATSCAN). The spatio-temporal evolutions of solids fractions in the consolidating sediments were continuously monitored. Since the interface between the sediment and the supernatant of the investigated slurries was blurred, an averaging procedure was employed to estimate their null-stress solids fractions (phi(g)s). Besides the rather slow settling for the high-phi(0) slurries, the basic settling characteristics resemble each other regardless of whether phi(0)>phi(g) or vice versa. The above-mentioned experimental data reveal that the investigated slurries are neither purely elastic nor purely plastic in rheological behavior. On contrary to most model works a blurred supernatant-sediment interface makes difficulty in the gel point determination. During initial settling the high-phi(0) slurries clearly exhibit a finite yield stress to resist deformation. That is, the slurries are plastic fluids. However, the network structure in the slurries deteriorates gradually in the subsequent settling stage while the final, equilibrated sediment reveals a continuous distribution in solids fraction. Restated, the final sediment possesses as a purely elastic characteristic. The model parameters of theory by Buscall and White were regressed by the dynamic consolidating sediment data, while those by Tiller and Leu were obtained using the final equilibrated sediment data. Calculations from both models reveal that ball clay slurry is more compressible than is the kaolin slurry. The high-phi(S0) slurry would yield the less compressible sediment. PMID:16290348

  12. Batch Proving and Proof Scripting in PVS

    NASA Technical Reports Server (NTRS)

    Munoz, Cesar A.

    2007-01-01

    The batch execution modes of PVS are powerful, but highly technical, features of the system that are mostly accessible to expert users. This paper presents a PVS tool, called ProofLite, that extends the theorem prover interface with a batch proving utility and a proof scripting notation. ProofLite enables a semi-literate proving style where specification and proof scripts reside in the same file. The goal of ProofLite is to provide batch proving and proof scripting capabilities to regular, non-expert, users of PVS.

  13. Development of adsorbent for the simultaneous removal of organic and inorganic contaminants from aqueous solution.

    PubMed

    Choi, J W; Chung, S G; Hong, S W; Kim, D J; Lee, S H

    2011-01-01

    In this study, a modified adsorbent, alginate complex beads, was prepared and applied to the removal of mixed contaminants from wastewater. The alginate complex beads were generated by the immobilization of powdered activated carbon and synthetic zeolites onto alginate gel beads, which were then dried at 110 °C for 20 h until the diameter had been reduced to 1 mm. This dry technique increased the hardness of the adsorbent to assure its durability and application. The adsorption onto the alginate complex beads of organic and inorganic compounds, as target contaminants, was investigated by performing both equilibrium and kinetic batch experiments. From the adsorption isotherms, according to the Langmuir equation, the alginate complex bead was capable of effectively removing benzene, toluene, zinc and cadmium. From kinetic batch experiments, the removal efficiencies of benzene, toluene, zinc and cadmium were found to be 66.5, 92.4, 74.1 and 76.7%, respectively, for initial solution concentrations of 100 mg L(-1). The results indicated that the adsorbent developed in this study has the potential to be a promising material for the removal of mixed pollutants from industrial wastewater or contaminated groundwater. PMID:22020474

  14. Complete braided adsorbent for marine testing to demonstrate 3g-U/kg-adsorbent

    SciTech Connect

    Janke, Chris; Yatsandra, Oyola; Mayes, Richard; none,; Gill, Gary; Li-Jung, Kuo; Wood, Jordana; Sadananda, Das

    2014-04-30

    ORNL has manufactured four braided adsorbents that successfully demonstrated uranium adsorption capacities ranging from 3.0-3.6 g-U/kg-adsorbent in marine testing at PNNL. Four new braided and leno woven fabric adsorbents have also been prepared by ORNL and are currently undergoing marine testing at PNNL.

  15. Fluorescence dynamics of microsphere-adsorbed sunscreens

    NASA Astrophysics Data System (ADS)

    Krishnan, R.

    2005-03-01

    Sunscreens are generally oily substances which are prepared in organic solvents, emulsions or dispersions with micro- or nanoparticles. These molecules adsorb to and integrate into skin cells. In order to understand the photophysical properties of the sunscreen, we compare steady-state and time-resolved fluorescence in organic solvent of varying dielectric constant ɛ and adsorbed to polystyrene microspheres and dispersed in water. Steady-state fluorescence is highest and average fluorescence lifetime longest in toluene, the solvent of lowest ɛ. However, there is no uniform dependence on ɛ. Sunscreens PABA and padimate-O show complex emission spectra. Microsphere-adsorbed sunscreens exhibit highly non-exponential decay, illustrative of multiple environments of the adsorbed molecule. The heterogeneous fluorescence dynamics likely characterizes sunscreen adsorbed to cells.

  16. Nanovalved Adsorbents for CH4 Storage.

    PubMed

    Song, Zhuonan; Nambo, Apolo; Tate, Kirby L; Bao, Ainan; Zhu, Minqi; Jasinski, Jacek B; Zhou, Shaojun J; Meyer, Howard S; Carreon, Moises A; Li, Shiguang; Yu, Miao

    2016-05-11

    A novel concept of utilizing nanoporous coatings as effective nanovalves on microporous adsorbents was developed for high capacity natural gas storage at low storage pressure. The work reported here for the first time presents the concept of nanovalved adsorbents capable of sealing high pressure CH4 inside the adsorbents and storing it at low pressure. Traditional natural gas storage tanks are thick and heavy, which makes them expensive to manufacture and highly energy-consuming to carry around. Our design uses unique adsorbent pellets with nanoscale pores surrounded by a coating that functions as a valve to help manage the pressure of the gas and facilitate more efficient storage and transportation. We expect this new concept will result in a lighter, more affordable product with increased storage capacity. The nanovalved adsorbent concept demonstrated here can be potentially extended for the storage of other important gas molecules targeted for diverse relevant functional applications. PMID:27124722

  17. NOx adsorber and method of regenerating same

    SciTech Connect

    Endicott, Dennis L.; Verkiel, Maarten; Driscoll, James J.

    2007-01-30

    New technologies, such as NOx adsorber catalytic converters, are being used to meet increasingly stringent regulations on undesirable emissions, including NOx emissions. NOx adsorbers must be periodically regenerated, which requires an increased fuel consumption. The present disclosure includes a method of regenerating a NOx adsorber within a NOx adsorber catalytic converter. At least one sensor positioned downstream from the NOx adsorber senses, in the downstream exhaust, at least one of NOx, nitrous oxide and ammonia concentrations a plurality of times during a regeneration phase. The sensor is in communication with an electronic control module that includes a regeneration monitoring algorithm operable to end the regeneration phase when a time rate of change of the at least one of NOx, nitrous oxide and ammonia concentrations is after an expected plateau region begins.

  18. Separation of the attractive and repulsive contributions to the adsorbate-adsorbate interactions of polar adsorbates on Si(100)

    NASA Astrophysics Data System (ADS)

    Lin, Ying-Hsiu; Jeng, Horng-Tay; Lin, Deng-Sung

    2015-11-01

    Dissociative adsorption of H2O, NH3, CH3OH and CH3NH2 polar molecules on the Si(100) surface results in a 1:1 mixture of two adsorbates (H and multi-atomic fragment A = OH, NH2, CH3O, CH3NH, respectively) on the surface. By using density functional theory (DFT) calculations, the adsorption geometry, the total energies and the charge densities for various possible ordered structures of the mixed adsorbate layer have been found. Analyzing the systematic trends in the total energies unveils concurrently the nearest-neighbor interactions ENN and the next nearest-neighbor interactions ENNN between two polar adsorbates A. In going from small to large polar adsorbates, ENN's exhibit an attractive-to-repulsive crossover behavior, indicating that they include competing attractive and repulsive contributions. Exploration of the charge density distributions allows the estimation of the degree of charge overlapping between immediately neighboring A's, the resulting contribution of the steric repulsions, and that of the attractive interactions to the corresponding ENN's. The attractive contributions to nearest neighboring adsorbate-adsorbate interactions between the polar adsorbates under study are shown to result from hydrogen bonds or dipole-dipole interactions.

  19. Analysis of Adsorbate-Adsorbate and Adsorbate-Adsorbent Interactions to Decode Isosteric Heats of Gas Adsorption.

    PubMed

    Madani, S Hadi; Sedghi, Saeid; Biggs, Mark J; Pendleton, Phillip

    2015-12-21

    A qualitative interpretation is proposed to interpret isosteric heats of adsorption by considering contributions from three general classes of interaction energy: fluid-fluid heat, fluid-solid heat, and fluid-high-energy site (HES) heat. Multiple temperature adsorption isotherms are defined for nitrogen, T=(75, 77, 79) K, argon at T=(85, 87, 89) K, and for water and methanol at T=(278, 288, 298) K on a well-characterized polymer-based, activated carbon. Nitrogen and argon are subjected to isosteric heat analyses; their zero filling isosteric heats of adsorption are consistent with slit-pore, adsorption energy enhancement modelling. Water adsorbs entirely via specific interactions, offering decreasing isosteric heat at low pore filling followed by a constant heat slightly in excess of water condensation enthalpy, demonstrating the effects of micropores. Methanol offers both specific adsorption via the alcohol group and non-specific interactions via its methyl group; the isosteric heat increases at low pore filling, indicating the predominance of non-specific interactions. PMID:26538339

  20. Inorganic chemically active adsorbents (ICAAs)

    SciTech Connect

    Ally, M.R.; Tavlarides, L.

    1997-10-01

    Oak Ridge National Laboratory (ORNL) researchers are developing a technology that combines metal chelation extraction technology and synthesis chemistry. They begin with a ceramic substrate such as alumina, titanium oxide or silica gel because they provide high surface area, high mechanical strength, and radiolytic stability. One preparation method involves silylation to hydrophobize the surface, followed by chemisorption of a suitable chelation agent using vapor deposition. Another route attaches newly designed chelating agents through covalent bonding by the use of coupling agents. These approaches provide stable and selective, inorganic chemically active adsorbents (ICAAs) tailored for removal of metals. The technology has the following advantages over ion exchange: (1) higher mechanical strength, (2) higher resistance to radiation fields, (3) higher selectivity for the desired metal ion, (4) no cation exchange, (5) reduced or no interference from accompanying anions, (6) faster kinetics, and (7) easy and selective regeneration. Target waste streams include metal-containing groundwater/process wastewater at ORNL`s Y-12 Plant (multiple metals), Savannah River Site (SRS), Rocky Flats (multiple metals), and Hanford; aqueous mixed wastes at Idaho National Engineering Laboratory (INEL); and scrubber water generated at SRS and INEL. Focus Areas that will benefit from this research include Mixed Waste, and Subsurface Contaminants.

  1. Separation of Lanthanoids by SiO{sub 2}-P Adsorbent Impregnated with Extractants - 13103

    SciTech Connect

    Yamanishi, Kei; Mimura, Hitoshi; Usuda, Shigekazu; Sasaki, Yuji; Morita, Yasuji

    2013-07-01

    The adsorption and separation properties of lanthanoids (Ln) were investigated for the mutual separation of trivalent minor actinoids (MA) by using different adsorbents of hydrophobic extractant/SiO{sub 2}-P in solutions of hydrophilic extractant/HNO{sub 3}. The synergistic effect by use of the hydrophobic and hydrophilic extractants was evaluated by batch and column experiments. The results of batch experiments showed the synergistic effect which lowered the K{sub d} values of Ln. In column experiments, effective mutual separation between Nd and Sm was demonstrated. These results suggest that the mutual separation between Am and Cm is possible because the K{sub d} values of Am and Cm are probably similar to those of Nd and Sm. (authors)

  2. Biotransformation of pink water TNT on the surface of a low-cost adsorbent pine bark.

    PubMed

    Chusova, O; Nõlvak, H; Odlare, M; Truu, J; Truu, M; Oopkaup, K; Nehrenheim, E

    2015-09-01

    This two-week anaerobic batch study evaluated 2,4,6-trinitrotoluene (TNT) removal efficiency from industrial pink water by (1) adsorption on low-cost adsorbent pine bark, and (2) adsorption coupled with TNT biotransformation by specialised microbial communities. Samples of the supernatant and acetonitrile extracts of pine bark were analysed by HPLC, while the composition of the bacterial community of the experimental batches, inocula and pine bark were profiled by high-throughput sequencing the V6 region of the bacterial 16S rRNA gene. Integrated adsorption and biotransformation proved to be the most efficient method for TNT removal from pink water. The type of applied inoculum had a profound effect on TNT removal efficiencies and microbial community structures, which were dominated by phylotypes belonging to the Enterobacteriaceae family. The analysis of acetonitrile extracts of pine bark supported the hypothesis that the microbial community indigenous to pine bark has the ability to degrade TNT. PMID:26142875

  3. Site blocking effects on adsorbed polyacrylamide conformation

    NASA Astrophysics Data System (ADS)

    Brotherson, Brett A.

    The use of polymers as flocculating additives is a common practice in many manufacturing environments. However, exactly how these polymers interact with surfaces is relatively unknown. One specific topic which is thought to be very important to flocculation is an adsorbed polymer's conformation. Substantial amounts of previous work, mainly using simulations, have been performed to elucidate the theory surrounding adsorbed polymer conformations. Yet, there is little experimental work which directly verifies current theory. In order to optimize the use of polymer flocculants in industrial applications, a better understanding of an adsorbed polymer's conformation on a surface beyond theoretical simulations is necessary. This work looks specifically at site blocking, which has a broad impact on flocculation, adsorption, and surface modification, and investigated its effects on the resulting adsorbed polymer conformation. Experimental methods which would allow direct determination of adsorbed polymer conformational details and be comparable with previous experimental results were first determined or developed. Characterization of an adsorbed polymer's conformation was then evaluated using dynamic light scattering, a currently accepted experimental technique to examine this. This commonly used technique was performed to allow the comparison of this works results with past literature. Next, a new technique using atomic force microscopy was developed, building on previous experimental techniques, to allow the direct determination of an adsorbed polymer's loop lengths. This method also was able to quantify changes in the length of adsorbed polymer tails. Finally, mesoscopic simulation was attempted using dissipative particle dynamics. In order to determine more information about an adsorbed polymer's conformation, three different environmental factors were analyzed: an adsorbed polymer on a surface in water, an adsorbed polymer on a surface in aqueous solutions of varying

  4. Comparison between Brazilian agro-wastes and activated carbon as adsorbents to remove Ni(II) from aqueous solutions.

    PubMed

    Dotto, Guilherme Luiz; Meili, Lucas; de Souza Abud, Ana Karla; Tanabe, Eduardo Hiromitsu; Bertuol, Daniel Assumpção; Foletto, Edson Luiz

    2016-01-01

    This research was performed to find an alternative, low-cost, competitive, locally available and efficient adsorbent to treat nickel (Ni) containing effluents. For this purpose, several Brazilian agro-wastes like sugarcane bagasse (SCB), passion fruit wastes (PFW), orange peel (OP) and pineapple peel (PP) were compared with an activated carbon (AC). The adsorbents were characterized. Effects of fundamental factors affecting the adsorption were investigated using batch tests. Kinetic and equilibrium studies were performed using conventional models. It was verified that the adsorption was favored at pH of 6.0 for all agro-wastes, being dependent of the Ni speciation, point of zero charge and surface area of the adsorbents. The Ni removal percentage was in the following order: SCB > OP > AC > PFW > PP. From the kinetic viewpoint, the Elovich model was appropriate to fit the Ni adsorption onto SCB, while for the other adsorbents, the pseudo-first-order model was the most suitable. For all adsorbents, the Langmuir model was the more adequate to represent the equilibrium data, being the maximum adsorption capacities of 64.1 mg g(-1), 60.7 mg g(-1), 63.1 mg g(-1), 48.1 mg g(-1) and 64.3 mg g(-1) for SCB, PFW, OP, PP and AC, respectively. These results indicated that mainly SCB and OP can be used as alternative adsorbents to treat Ni containing effluents. PMID:27232408

  5. Removal of organic pollutants from aqueous solutions by adsorbents prepared from an agroalimentary by-product.

    PubMed

    Delval, Franck; Crini, Grégorio; Vebrel, Joël

    2006-11-01

    Two series of crosslinked starch polymers were tested for their ability to adsorb organic pollutants in aqueous solutions. The polymers were prepared by a crosslinking reaction of starch-enriched flour using epichlorohydrin as the crosslinking agent, without and in the presence of NH(4)OH. These polymers were used as sorbent materials for the removal of phenolic derivatives from wastewater. The influence of several parameters (kinetics, pH and polymer structure) on the sorption capacity was evaluated using the batch and the open column methods. Results of adsorption experiments showed that the starch-based materials exhibited high sorption capacities toward phenolic derivatives. The study of the kinetics of pollutant uptake revealed that the adsorbents presented a relatively fast rate of adsorption. The experimental data were examined using the Langmuir and Freundlich models and it was found that the Freundlich model appeared to fit the isotherm data better than the Langmuir model. PMID:16275061

  6. Pullulan Production by Aureobasidium pullulans ATCC 201253 Cells Adsorbed onto Cellulose Anion and Cation Exchangers

    PubMed Central

    West, Thomas P.

    2012-01-01

    The anion exchanger phosphocellulose and the cation exchanger triethylaminoethyl cellulose were used to immobilize cells of the fungus Aureobasidium pullulans ATCC 201253 and the adsorbed cells were subsequently investigated for their ability to produce the polysaccharide pullulan using batch fermentation. The cells adsorbed on the triethylaminoethyl cellulose at pH 7.5 produced higher pullulan levels than those cells immobilized on phosphocellulose at pH 4.0 for 2 cycles of 168 h at 30 °C. Relative to the initial cycle of 168 h, pullulan production by the cells immobilized on the triethylaminoethyl cellulose decreased slightly after 168 h of the second production cycle while pullulan production by the phosphocellulose-immobilized cells remained about the same after 168 h of the second production cycle. PMID:23762749

  7. Thermodynamic investigation of trichloroethylene adsorption in water-saturated microporous adsorbents

    SciTech Connect

    Farrell, J.; Hauck, B.; Jones, M.

    1999-08-01

    Adsorption of trichloroethylene (TCE) in adsorbents containing hydrophilic and hydrophobic micropores was investigated in order to determine the mechanisms responsible for TCE adsorption on mineral solids. A high-pressure liquid chromatography method was used to measure TCE adsorption isotherms on three microporous adsorbents. Silica gel and zeolite type NaX were used as hydrophilic model adsorbents, and hexamethyldisilazane (HMDS)-treated silica gel was used as a model hydrophobic adsorbent. Batch uptake and desorption isotherms were also measured on the hydrophilic silica gel. Uptake of TCE by all three adsorbents was linear over the concentration range investigated. However, the silica gel desorption isotherm was highly nonlinear, as indicated by its Freundlich isotherm exponent of 0.58. Capillary phase separation into hydrophobic micropores was postulated as being responsible for the isotherm hysteresis. Supporting this hypothesis was the conformance of the TCE adsorption isotherm to Dubinin-Radushkevitch volume filling of micropores theory. The enthalpies for TCE adsorption on all three solids were determined by van't Hoff analysis of distribution coefficients measured over a temperature range from 5 to 90 C. The TCE adsorption enthalpies on the silica gel and HMDS silica gel were exothermic, but on the zeolite adsorption was endothermic. High exothermic adsorption enthalpies on the silica gel adsorbents indicated that TCE adsorption was occurring in hydrophobic micropores, and that adsorption on surfaces with large radii of curvature contributed only minimally to the total uptake. This indicates that the predominant mechanism for TCE adsorption on these mineral solids is not partitioning into the vicinal water layer.

  8. 40 CFR 63.1408 - Aggregate batch vent stream provisions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... from all aggregate batch vent streams in the compliance demonstration required for reactor batch... comply with the mass emission limit for reactor batch process vents. ... 40 Protection of Environment 11 2010-07-01 2010-07-01 true Aggregate batch vent stream...

  9. Adsorption of Procion Red MX 8B using spent tea leaves as adsorbent

    NASA Astrophysics Data System (ADS)

    Heraldy, Eddy; Osa, Riesta Ramdhaniyati; Suryanti, Venty

    2016-02-01

    The adsorption of Procion Red MX 8B using spent tea leaves (STL) as adsorbent, has been studied by batch adsorption technique. The adsorbent was activated by NaOH 4% for 24 hours for delignification process. The adsorbent was characterized using FTIR to indetify the functional groups of cellulose was shown by uptake -OH, C-H and C-O. The optimum conditions of adsorption experiments were achieved when pH was set as 6 with contact time of 75 minutes and capacity of adsorption was 3.28 mg/g. The equilibrium data were fitted to Langmuir and Isotherm Freundlichs. The kinetic models, pseudo first order and pseudo second order were employed to describe the adsorption mechanism. The experimental results showed that the pseudo second order equation was the best model that described the adsorption behavior with the coefficient of correlation (R2) was equal higher than 0.99 The results suggested that STL had high potential to be used as effective adsorbent for Procion Red MX 8B removal.

  10. Fluoride removal from aqueous solution by Al(III)-Zr(IV) binary oxide adsorbent

    NASA Astrophysics Data System (ADS)

    Zhu, Jiuya; Lin, Xiaoyan; Wu, Pengwei; Zhou, Qiusheng; Luo, Xuegang

    2015-12-01

    In this study, a novel binary oxide adsorbent of Al2O3-ZrO2 was prepared via coprecipitation followed by calcination method, and the calcination temperatures were investigated. The adsorbent was characterized by XRD, EDX and XPS. The batch adsorption experiments were carried out at different parameters, such as solution pH, adsorbent dose, contact time, initial fluoride concentration and adsorption temperature, to evaluate the fluoride removal performance. The results showed that the adsorption isotherm was better described by the linear Langmuir model, and a maximum adsorption capacity was 114.54 mg/g. The adsorption kinetics was well fitted by the linear pseudo-second-order, and the correlation coefficient value (R2) was 0.997. The thermodynamic parameters of ΔH0, ΔS0 and ΔG0 were calculated, which showed that the fluoride adsorption process was spontaneous and exothermic. And the possible adsorption mechanism of the adsorbent for fluoride could involve the ligand-exchange and ion-exchange based on the results in the study.

  11. Adsorbed natural gas storage with activated carbon

    SciTech Connect

    Sun, Jian; Brady, T.A.; Rood, M.J.

    1996-12-31

    Despite technical advances to reduce air pollution emissions, motor vehicles still account for 30 to 70% emissions of all urban air pollutants. The Clean Air Act Amendments of 1990 require 100 cities in the United States to reduce the amount of their smog within 5 to 15 years. Hence, auto emissions, the major cause of smog, must be reduced 30 to 60% by 1998. Natural gas con be combusted with less pollutant emissions. Adsorbed natural gas (ANG) uses adsorbents and operates with a low storage pressure which results in lower capital costs and maintenance. This paper describes the production of an activated carbon adsorbent produced from an Illinois coal for ANG.

  12. States of water adsorbed on perindopril crystals

    NASA Astrophysics Data System (ADS)

    Stepanov, V. A.; Khmelevskaya, V. S.; Bogdanov, N. Yu.; Gorchakov, K. A.

    2011-10-01

    The relationship between the structural state of adsorbed water, the crystal structure of the substances, and the solubility of the perindopril salt C19H32N2O5 · C4H11N in water was studied by IR spectroscopy and X-ray diffractometry. The high-frequency shift of the stretching vibrations of adsorbed water and the solubility depend on the crystal structure of the drug substance. A reversible chemical reaction occurred between the adsorbed water and the perindopril salt.

  13. Volumetric Interpretation of Protein Adsorption: Capacity Scaling with Adsorbate Molecular Weight and Adsorbent Surface Energy

    PubMed Central

    Parhi, Purnendu; Golas, Avantika; Barnthip, Naris; Noh, Hyeran; Vogler, Erwin A.

    2009-01-01

    Silanized-glass-particle adsorbent capacities are extracted from adsorption isotherms of human serum albumin (HSA, 66 kDa), immunoglobulin G (IgG, 160 kDa), fibrinogen (Fib, 341 kDa), and immunoglobulin M (IgM, 1000 kDa) for adsorbent surface energies sampling the observable range of water wettability. Adsorbent capacity expressed as either mass-or-moles per-unit-adsorbent-area increases with protein molecular weight (MW) in a manner that is quantitatively inconsistent with the idea that proteins adsorb as a monolayer at the solution-material interface in any physically-realizable configuration or state of denaturation. Capacity decreases monotonically with increasing adsorbent hydrophilicity to the limit-of-detection (LOD) near τo = 30 dyne/cm (θ~65o) for all protein/surface combinations studied (where τo≡γlvocosθ is the water adhesion tension, γlvo is the interfacial tension of pure-buffer solution, and θ is the buffer advancing contact angle). Experimental evidence thus shows that adsorbent capacity depends on both adsorbent surface energy and adsorbate size. Comparison of theory to experiment implies that proteins do not adsorb onto a two-dimensional (2D) interfacial plane as frequently depicted in the literature but rather partition from solution into a three-dimensional (3D) interphase region that separates the physical surface from bulk solution. This interphase has a finite volume related to the dimensions of hydrated protein in the adsorbed state (defining “layer” thickness). The interphase can be comprised of a number of adsorbed-protein layers depending on the solution concentration in which adsorbent is immersed, molecular volume of the adsorbing protein (proportional to MW), and adsorbent hydrophilicity. Multilayer adsorption accounts for adsorbent capacity over-and-above monolayer and is inconsistent with the idea that protein adsorbs to surfaces primarily through protein/surface interactions because proteins within second (or higher

  14. A Batch Feeder for Inhomogeneous Bulk Materials

    NASA Astrophysics Data System (ADS)

    Vislov, I. S.; Kladiev, S. N.; Slobodyan, S. M.; Bogdan, A. M.

    2016-04-01

    The work includes the mechanical analysis of mechanical feeders and batchers that find application in various technological processes and industrial fields. Feeders are usually classified according to their design features into two groups: conveyor-type feeders and non-conveyor feeders. Batchers are used to batch solid bulk materials. Less frequently, they are used for liquids. In terms of a batching method, they are divided into volumetric and weighting batchers. Weighting batchers do not provide for sufficient batching accuracy. Automatic weighting batchers include a mass controlling sensor and systems for automatic material feed and automatic mass discharge control. In terms of operating principle, batchers are divided into gravitational batchers and batchers with forced feed of material using conveyors and pumps. Improved consumption of raw materials, decreased loss of materials, ease of use in automatic control systems of industrial facilities allows increasing the quality of technological processes and improve labor conditions. The batch feeder suggested by the authors is a volumetric batcher that has no comparable counterparts among conveyor-type feeders and allows solving the problem of targeted feeding of bulk material batches increasing reliability and hermeticity of the device.

  15. Kinetics of enzymatic hydrolysis of olive oil in batch and fed-batch systems.

    PubMed

    Cabral, Paloma Souza; Filho, Arion Zandoná; Voll, Fernando Augusto Pedersen; Corazza, Marcos Lúcio

    2014-07-01

    This work reports experimental data, kinetic modeling, and simulations of enzyme-catalyzed hydrolysis of olive oil. This reaction was performed in batch system and an ordered-sequential Bi Bi model was used to model the kinetic mechanism. A fed-batch system was proposed and experimental data were obtained and compared to the simulated values. The kinetic model used was able to correlate the experimental data, in which a satisfactory agreement between the experimental data and modeling results was obtained under different enzyme concentration and initial free water content. Therefore, the modeling allowed a better understanding of the reaction kinetics and affords a fed-batch simulation for this system. From the results obtained, it was observed that the fed-batch approach showed to be more advantageous when compared to the conventional batch system. PMID:24793196

  16. Quality and Batch-to-Batch Consistency of Original and Biosimilar Epoetin Products.

    PubMed

    Halim, Liem Andhyk; Brinks, Vera; Jiskoot, Wim; Romeijn, Stefan; Haselberg, Rob; Burns, Chris; Wadhwa, Meenu; Schellekens, Huub

    2016-02-01

    Comprehensive physicochemical characterization and biological assays are essential parts in assessing quality attributes of biologicals. Here, we compared the quality of different marketed recombinant human erythropoietin (epoetin) products: originators, Eprex and NeoRecormon as well as 2 biosimilars, Retacrit and Binocrit. In addition, assessment of batch-to-batch variability was included by collecting 2 or more batches of each product. Common assays which included sodium dodecyl sulfate-polyacrylamide gel electrophoresis, high-performance size-exclusion chromatography, asymmetrical flow field-flow fractionation, capillary zone electrophoresis, and potency testing were used. Of the tested products and among batches of single products, variations in epoetin content, isoform profiles, and potency were found. Ultimately, this study demonstrated the high quality of epoetin products with some degree of variation among products and batches, confirming the "similar but not identical" paradigm of biologicals. PMID:26869417

  17. Sample displacement batch chromatography of proteins.

    PubMed

    Kotasinska, Marta; Richter, Verena; Kwiatkowski, Marcel; Schlüter, Hartmut

    2014-01-01

    In downstream processing large scale chromatography plays an important role. For its development screening experiments followed by pilot plant chromatography are mandatory steps. Here we describe fast, simple, and inexpensive methods for establishing a preparative chromatography for the separation of complex protein mixtures, based on sample displacement batch chromatography. The methods are demonstrated by anion-exchange chromatography of a human plasma protein fraction (Cohn IV-4), including the screening step and scaling up of the chromatography by a factor of 100. The results of the screening experiments and the preparative chromatography are monitored by SDS-PAGE electrophoresis. In summary we provide a protocol which should be easily adaptable for the chromatographic large scale purification of other proteins, in the laboratory as well as in industry for commercial manufacturing. For the latter these protocols cover the initial piloting steps for establishing a sample batch chromatography based on packed columns rather than batch chromatography. PMID:24648085

  18. IR investigations of surfaces and adsorbates

    SciTech Connect

    Gwyn Williams

    2001-12-10

    Synchrotron infrared reflection-absorption measurements on single crystal metal surfaces with adsorbates have led to the determination of many key parameters related to the bonding vibrational modes and the dynamics of adsorbates. In particular, energy couplings between electrons and adsorbate motion have been shown to be a dominant mechanism on metal surfaces. Excellent agreement has been obtained with calculations for many of the observations, and the synergy between theory and experiment has led to a deeper understanding of the roles of electrons and phonons in determining the properties of interfaces and their roles in phenomena as diverse as friction, lubrication, catalysis and adhesion. Nonetheless, as the experiments are pushed harder, to describe such effects as co-adsorbed systems, disagreements continue to challenge the theory and our comprehension also is still evolving.

  19. PERVAPORATION USING ADSORBENT-FILLED MEMBRANES

    EPA Science Inventory

    Membranes containing selective fillers, such as zeolites and activated carbon, can improve the separation by pervaporation. Applications of adsorbent-filled membranes in pervaporation have been demonstrated by a number of studies. These applications include removal of organic co...

  20. Examining Adsorbed Polymer Conformations with Fluorescence Imaging

    NASA Astrophysics Data System (ADS)

    Parkes, Maria; Chennaoui, Mourad; Wong, Janet; Tribology Group, Dept. of Mechanical Engineering Team

    2011-03-01

    The conformation of adsorbed polymers can have significant impact on their properties such as dynamics and elasticity as well as their ability to take part in reactions with other molecules. Experimental research to determine adsorbed polymer conformation has relied mainly on atomic force microscopy (AFM) studies. During an AFM scan, the contact between the scanning probe and the polymer could affect the polymer conformation, particularly where parts of the polymer might have formed projected loops and tails. In this work, conformations of model polymers are examined with total internal reflection fluorescence microscopy (TIRFM). The advantage of TIRFM over AFM is that TIRFM is a non contact technique. Lambda DNA labelled along its length with fluorescent probes was adsorbed in a projected 2D -- 3D state. With TIRFM, the relationship between intensity and depth was used as a basis to determine how the conformation of the adsorbed polymers evolved with time using our custom algorithm.

  1. Dispersed-phase adsorbents for biotechnology applications

    SciTech Connect

    Scott, C.D.

    1987-01-01

    A new type of adsorbent material has been developed in which very small adsorbent particles are entrapped in a hydrocolloidal gel matrix that is formed into small, monodisperse spherical beads. Examples of applications of this type of material include dispersed, hydrous transition metal oxides that can be used for the retention of biocatalysts, such as enzymes, and certain microorganisms or microbial fragments that can be dispersed into the gel matrix to accumulate and isolate various dissolved metals. 7 refs., 2 figs., 2 tabs.

  2. Regenerable activated bauxite adsorbent alkali monitor probe

    DOEpatents

    Lee, Sheldon H. D.

    1992-01-01

    A regenerable activated bauxite adsorber alkali monitor probe for field applications to provide reliable measurement of alkali-vapor concentration in combustion gas with special emphasis on pressurized fluidized-bed combustion (PFBC) off-gas. More particularly, the invention relates to the development of a easily regenerable bauxite adsorbent for use in a method to accurately determine the alkali-vapor content of PFBC exhaust gases.

  3. Hydrophobic Porous Material Adsorbs Small Organic Molecules

    NASA Technical Reports Server (NTRS)

    Sharma, Pramod K.; Hickey, Gregory S.

    1994-01-01

    Composite molecular-sieve material has pore structure designed specifically for preferential adsorption of organic molecules for sizes ranging from 3 to 6 angstrom. Design based on principle that contaminant molecules become strongly bound to surface of adsorbent when size of contaminant molecules is nearly same as that of pores in adsorbent. Material used to remove small organic contaminant molecules from vacuum systems or from enclosed gaseous environments like closed-loop life-support systems.

  4. Mesoporous Silica: A Suitable Adsorbent for Amines

    PubMed Central

    2009-01-01

    Mesoporous silica with KIT-6 structure was investigated as a preconcentrating material in chromatographic systems for ammonia and trimethylamine. Its adsorption capacity was compared to that of existing commercial materials, showing its increased adsorption power. In addition, KIT-6 mesoporous silica efficiently adsorbs both gases, while none of the employed commercial adsorbents did. This means that KIT-6 Mesoporous silica may be a good choice for integrated chromatography/gas sensing micro-devices. PMID:20628459

  5. Regenerable activated bauxite adsorbent alkali monitor probe

    DOEpatents

    Lee, S.H.D.

    1992-12-22

    A regenerable activated bauxite adsorber alkali monitor probe for field applications to provide reliable measurement of alkali-vapor concentration in combustion gas with special emphasis on pressurized fluidized-bed combustion (PFBC) off-gas. More particularly, the invention relates to the development of a easily regenerable bauxite adsorbent for use in a method to accurately determine the alkali-vapor content of PFBC exhaust gases. 6 figs.

  6. Thiophilic adsorbents for RIA and ELISA procedures.

    PubMed

    Oscarsson, S; Chaga, G; Porath, J

    1991-10-25

    Three types of agarose derivatives have been prepared and investigated as adsorbents for radioimmunoassay and ELISA analysis. The analytical systems were evaluated using beta 2 microglobulin as a model. After a competitive reaction between the immunocomponents in solution, the formed immune complexes were adsorbed onto the adsorbent in the presence of 0.5 M potassium sulfate in 0.1 M Tris, pH 7.5. The binding constant between the interaction site on human IgG and the adsorbent 3-(2-pyridylthio)-2-hydroxypropylagarose (Py-S-gel) was determined to be 1.5 x 10(7) M-1 and the binding capacity was 20 mg/ml gel. The immune complex was desorbed by deleting potassium sulfate from the buffer, and only 0.5% of the total applied protein remained after washing the adsorbent with 0.5 M NaOH. The same adsorbent can be used repetitively with different systems. PMID:1940385

  7. Photochemistry of Nitrate Adsorbed on Mineral Dust

    NASA Astrophysics Data System (ADS)

    Gankanda, A.; Grassian, V. H.

    2013-12-01

    Mineral dust particles in the atmosphere are often associated with adsorbed nitrate from heterogeneous reactions with nitrogen oxides including HNO3 and NO2. Although nitrate ion is a well-studied chromophore in natural waters, the photochemistry of adsorbed nitrate on mineral dust particles is yet to be fully explored. In this study, wavelength dependence of the photochemistry of adsorbed nitrate on different model components of mineral dust aerosol has been investigated using transmission FTIR spectroscopy. Al2O3, TiO2 and NaY zeolite were used as model systems to represent non-photoactive oxides, photoactive semiconductor oxides and porous materials respectively, present in mineral dust aerosol. In this study, adsorbed nitrate is irradiated with 254 nm, 310 nm and 350 nm narrow band light. In the irradiation with narrow band light, NO2 is the only detectable gas-phase product formed from nitrate adsorbed on Al2O3 and TiO2. The NO2 yield is highest at 310 nm for both Al2O3 and TiO2. Unlike Al2O3 and TiO2, in zeolite, adsorbed nitrate photolysis to nitrite is observed only at 310 nm during narrow band irradiation. Moreover gas phase products were not detected during nitrate photolysis in zeolite at all three wavelengths. The significance of these differences as related to nitrate photochemistry on different mineral dust components will be highlighted.

  8. Mineral Adsorbents for Removal of Metals in Urban Runoff

    NASA Astrophysics Data System (ADS)

    Bjorklund, Karin; Li, Loretta

    2014-05-01

    The aim of this research was to determine the capacity of four different soil minerals to adsorb metals frequently detected in urban runoff. These are low-cost, natural and commercially available soil minerals. Contaminated surface runoff from urban areas is a major cause of concern for water quality and aquatic ecosystems worldwide. Pollution in urban areas is generated by a wide array of non-point sources, including vehicular transportation and building materials. Some of the most frequently detected pollutants in urban runoff are metals. Exhaust gases, tire wear and brake linings are major sources of such metals as Pb, Zn and Cu, while impregnated wood, plastics and galvanized surfaces may release As, Cd, Cr and Zn. Many metals have toxic effects on aquatic plants and animals, depending on metal speciation and bioavailability. The removal efficiency of pollutants in stormwater depends on treatment practices and on the properties the pollutant. The distribution of metals in urban runoff has shown, for example, that Pb is predominantly particle-associated, whereas Zn and Cd are present mainly in dissolved form. Many metals are also attached to colloids, which may act as carriers for contaminants, thereby facilitating their transport through conventional water treatment processes. Filtration of stormwater is one of the most promising techniques for removal of particulates, colloidal and truly dissolved pollutants, provided that effective filtration and adsorption media are used. Filtration and infiltration are used in a wide array of stormwater treatment methods e.g. porous paving, infiltration drains and rain gardens. Several soil minerals were investigated for their potential as stormwater filter materials. Laboratory batch tests were conducted to determine the adsorption capacity of these minerals. A synthetic stormwater was tested, with spiked concentrations corresponding to levels reported in urban runoff, ranging from 50-1,500 µg/L for Zn; 5-250 µg/L for Cu

  9. Removal of zearalenone toxin from synthetics gastric and body fluids using talc and diatomite: a batch kinetic study.

    PubMed

    Sprynskyy, Myroslav; Gadzała-Kopciuch, Renata; Nowak, Karolina; Buszewski, Bogusław

    2012-06-01

    Adsorption kinetics of zearalenone (ZEA) toxin from synthetic gastric fluid (SGF) and synthetic body fluid (SBF) by talc and diatomite was studied in the batch experiments. Chemical composition, morphology and structure of the used adsorbents were examined by scanning electron microscopy, FTIR spectroscopy and low-temperature nitrogen adsorption/desorption method. High performance liquid chromatography (HPLC) method was used for ZEA determining. The study results showed that ZEA is more effectively adsorbed on the talc (73% and 54% from SGF and SBF respectively). The efficiency on the diatomite was lower (53% and 42% from SGF and SBF respectively). The first order kinetics model was applied to describe the adsorption process. Rate of the ZEA adsorption from SGF is very rapid initially with about 95% of amount of the toxin adsorbed during first 5 min, while ZEA is adsorbed from SBF in two steps. The values of determined Gibbs free energy of adsorption (from -13 to -17 kJ/mol) indicated that adsorption of ZEA toxin by the both adsorbents are spontaneous and exothermic. PMID:22326340

  10. Production of nattokinase by batch and fed-batch culture of Bacillus subtilis.

    PubMed

    Cho, Young-Han; Song, Jae Yong; Kim, Kyung Mi; Kim, Mi Kyoung; Lee, In Young; Kim, Sang Bum; Kim, Hyeon Shup; Han, Nam Soo; Lee, Bong Hee; Kim, Beom Soo

    2010-09-30

    Nattokinase was produced by batch and fed-batch culture of Bacillus subtilis in flask and fermentor. Effect of supplementing complex media (peptone, yeast extract, or tryptone) was investigated on the production of nattokinase. In flask culture, the highest cell growth and nattokinase activity were obtained with 50 g/L of peptone supplementation. In this condition, nattokinase activity was 630 unit/ml at 12 h. In batch culture of B. subtilis in fermentor, the highest nattokinase activity of 3400 unit/ml was obtained at 10h with 50 g/L of peptone supplementation. From the batch kinetics data, it was shown that nattokinase production was growth-associated and culture should be harvested before stationary phase for maximum nattokinase production. In fed-batch culture of B. subtilis using pH-stat feeding strategy, cell growth (optical density monitored at 600 nm) increased to ca. 100 at 22 h, which was 2.5 times higher than that in batch culture. The highest nattokinase activity was 7100 unit/ml at 19 h, which was also 2.1 times higher than that in batch culture. PMID:20541632

  11. JOB BUILDER remote batch processing subsystem

    NASA Technical Reports Server (NTRS)

    Orlov, I. G.; Orlova, T. L.

    1980-01-01

    The functions of the JOB BUILDER remote batch processing subsystem are described. Instructions are given for using it as a component of a display system developed by personnel of the System Programming Laboratory, Institute of Space Research, USSR Academy of Sciences.

  12. RLIN Product Batch: Fundamental Design Concepts.

    ERIC Educational Resources Information Center

    Crawford, Walt

    1984-01-01

    Considers fundamental decisions that shaped the output products of Research Libraries Information Network. Product Batch was designed using single data definition (RMARC) combined with standard PL/I, modular programing techniques, program documentation. Choice of software and programing languages, other design aspects (accountability, count…

  13. Insight into the adsorption of PPCPs by porous adsorbents: Effect of the properties of adsorbents and adsorbates.

    PubMed

    Zhu, Zengyin; Xie, Jiawen; Zhang, Mancheng; Zhou, Qing; Liu, Fuqiang

    2016-07-01

    Adsorption is an efficient method for removal of pharmaceuticals and personal care products (PPCPs). Magnetic resins are efficient adsorbents for water treatment and exhibit potential for PPCP removal. In this study, the magnetic hypercrosslinked resin Q100 was used for adsorption of PPCPs. The adsorption behavior of this resin was compared with those of two activated carbons, namely, Norit and F400D. Norit exhibited the fastest adsorption kinetics, followed by Q100. Norit featured a honeycomb shape and long-range ordered pore channels, which facilitated the diffusion of PPCPs. Moreover, the large average pore size of Q100 reduced diffusion resistance. The adsorbed amounts of 11 PPCPs on the three adsorbents increased with increasing adsorbate hydrophobicity. For Q100, a significant linear correlation was observed between the adsorption performance for PPCPs and hydrophobicity (logD value) of adsorbates (R(2) = 0.8951); as such, PPCPs with high logD values (>1.69) could be efficiently removed. Compared with those of Norit and F400D, the adsorption performance of Q100 was less affected by humic acid because of the dominant hydrophobic interaction. Furthermore, Q100 showed improved regeneration performance, which renders it promising for PPCP removal in practical applications. PMID:27131811

  14. Removal of uranium from aqueous solution by a low cost and high-efficient adsorbent

    NASA Astrophysics Data System (ADS)

    Liu, Yun-Hai; Wang, You-Qun; Zhang, Zhi-Bin; Cao, Xiao-Hong; Nie, Wen-Bin; Li, Qin; Hua, Rong

    2013-05-01

    In this study, a low-cost and high-efficient carbonaceous adsorbent (HTC-COOH) with carboxylic groups was developed for U(VI) removal from aqueous solution compared with the pristine hydrothermal carbon (HTC). The structure and chemical properties of resultant adsorbents were characterized by Scanning electron microscope (SEM), N2 adsorption-desorption, Fourier transform-infrared spectra (FT-IR) and acid-base titration. The key factors (solution pH, contact time, initial U(VI) concentrations and temperature) affected the adsorption of U(VI) on adsorbents were investigated using batch experiments. The adsorption of U(VI) on HTC and HTC-COOH was pH-dependent, and increased with temperature and initial ion concentration. The adsorption equilibrium of U(VI) on adsorbents was well defined by the Langmuir isothermal equation, and the monolayer adsorption capacity of HTC-COOH was found to be 205.8 mg/g. The kinetics of adsorption was very in accordance with the pseudo-second-order rate model. The adsorption processes of U(VI) on HTC and HTC-COOH were endothermic and spontaneous in nature according to the thermodynamics of adsorption. Furthermore, HTC-COOH could selectively adsorption of U(VI) in aqueous solution containing co-existing ions (Mg2+, Co2+, Ni2+, Zn2+ and Mn2+). From the results of the experiments, it is found that the HTC-COOH is a potential adsorbent for effective removal of U(VI) from polluted water.

  15. Black Molecular Adsorber Coatings for Spaceflight Applications

    NASA Technical Reports Server (NTRS)

    Abraham, Nithin Susan; Hasegawa, Mark Makoto; Straka, Sharon A.

    2014-01-01

    The molecular adsorber coating is a new technology that was developed to mitigate the risk of on-orbit molecular contamination on spaceflight missions. The application of this coating would be ideal near highly sensitive, interior surfaces and instruments that are negatively impacted by outgassed molecules from materials, such as plastics, adhesives, lubricants, epoxies, and other similar compounds. This current, sprayable paint technology is comprised of inorganic white materials made from highly porous zeolite. In addition to good adhesion performance, thermal stability, and adsorptive capability, the molecular adsorber coating offers favorable thermal control characteristics. However, low reflectivity properties, which are typically offered by black thermal control coatings, are desired for some spaceflight applications. For example, black coatings are used on interior surfaces, in particular, on instrument baffles for optical stray light control. Similarly, they are also used within light paths between optical systems, such as telescopes, to absorb light. Recent efforts have been made to transform the white molecular adsorber coating into a black coating with similar adsorptive properties. This result is achieved by optimizing the current formulation with black pigments, while still maintaining its adsorption capability for outgassing control. Different binder to pigment ratios, coating thicknesses, and spray application techniques were explored to develop a black version of the molecular adsorber coating. During the development process, coating performance and adsorption characteristics were studied. The preliminary work performed on black molecular adsorber coatings thus far is very promising. Continued development and testing is necessary for its use on future contamination sensitive spaceflight missions.

  16. Size selective hydrophobic adsorbent for organic molecules

    NASA Technical Reports Server (NTRS)

    Sharma, Pramod K. (Inventor); Hickey, Gregory S. (Inventor)

    1997-01-01

    The present invention relates to an adsorbent formed by the pyrolysis of a hydrophobic silica with a pore size greater than 5 .ANG., such as SILICALITE.TM., with a molecular sieving polymer precursor such as polyfurfuryl alcohol, polyacrylonitrile, polyvinylidene chloride, phenol-formaldehyde resin, polyvinylidene difluoride and mixtures thereof. Polyfurfuryl alcohol is the most preferred. The adsorbent produced by the pyrolysis has a silicon to carbon mole ratio of between about 10:1 and 1:3, and preferably about 2:1 to 1:2, most preferably 1:1. The pyrolysis is performed as a ramped temperature program between about 100.degree. and 800.degree. C., and preferably between about 100.degree. and 600.degree. C. The present invention also relates to a method for selectively adsorbing organic molecules having a molecular size (mean molecular diameter) of between about 3 and 6 .ANG. comprising contacting a vapor containing the small organic molecules to be adsorbed with the adsorbent composition of the present invention.

  17. Trivalent chromium removal from aqueous solutions by a sol–gel synthesized silica adsorbent functionalized with sulphonic acid groups

    SciTech Connect

    Gomez-Gonzalez, Sergio Efrain; Carbajal-Arizaga, Gregorio Guadalupe; Manriquez-Gonzalez, Ricardo; De la Cruz-Hernandez, Wencel; Gomez-Salazar, Sergio

    2014-11-15

    Highlights: • Corpuscular sulphonic acid-functionalized silica holds improved uptake of chromium. • Mesopores on adsorbent facilitate (CH{sub 3}COO){sub 2}Cr{sup +} ion uptake on sulphonate sites. • Formation of chromium acetate sulphonate complex proposed from XPS results. • Fixed bed chromium uptake results suggest potential industrial use. - Abstract: A high capacity hybrid silica adsorbent was synthesized via sol–gel processing with sulphonic acid groups as trivalent chromium complex ions chelators from aqueous solutions. The synthesis included co-condensation of tetraethoxysilane (TEOS) with 3-(mercaptopropyl)trimethoxysilane (MPS), and oxidation of thiol to sulphonic acid groups. Chromium uptake kinetic, batch and fixed-bed experiments were performed to assess the removal of this metal from aqueous solutions. {sup 13}C, {sup 29}Si CPMAS NMR, FTIR, XPS were used to characterize the adsorbent structure and the nature of chromium complexes on the adsorbent surface. Chromium maximum uptake was obtained at pH 3 (72.8 mg/g). Elemental analysis results showed ligand density of 1.48 mmol sulphonic groups/g. About 407 mL of Cr(III) solution (311 mg/L) were treated to breakthrough point reaching ≤0.06 mg/L at the effluent. These results comply with USEPA regulation for chromium concentration in drinking water (≤0.1 mg/L). The adsorbent shows potential to be used in chromium separations to the industrial level.

  18. Removal of Acid Orange 7 from aqueous solution using magnetic graphene/chitosan: a promising nano-adsorbent.

    PubMed

    Sheshmani, Shabnam; Ashori, Alireza; Hasanzadeh, Saeed

    2014-07-01

    Magnetic graphene/chitosan (MGCh) nanocomposite was fabricated through a facile chemical route and its application as a new adsorbent for Acid Orange 7 (AO7) removal was also investigated. After synthesis, the full characterization with various techniques (FTIR, XRD, VSM, and SEM) was achieved revealing many possible interactions/forces of dye-composite system. The results showed that, benefiting from the surface property of graphene oxide, the abundant amino and hydroxyl functional groups of chitosan, and from the magnetic property of Fe3O4, the adsorbent possesses quite a good and versatile adsorption capacity to the dye under investigation, and can be easily and rapidly extracted from water by magnetic attraction. The maximum absorption capacity was reached at initial pH 3 and 120min contact time. The batch adsorption experiments showed that the adsorption of the AO7 is considerably dependent on pH of milieu, amount of adsorbent, and contact time. The adsorption kinetics and isotherms were investigated to indicate that the kinetic and equilibrium adsorption were well-described by pseudo-first order kinetic and Langmuir isotherm model, respectively. The adsorption behavior suggested that the adsorbent surface was homogeneous in nature. The study suggests that the MGCh is a promising nano adsorbent for removal of anionic azo dyes from aqueous solution. PMID:24813679

  19. Method for modifying trigger level for adsorber regeneration

    DOEpatents

    Ruth, Michael J.; Cunningham, Michael J.

    2010-05-25

    A method for modifying a NO.sub.x adsorber regeneration triggering variable. Engine operating conditions are monitored until the regeneration triggering variable is met. The adsorber is regenerated and the adsorbtion efficiency of the adsorber is subsequently determined. The regeneration triggering variable is modified to correspond with the decline in adsorber efficiency. The adsorber efficiency may be determined using an empirically predetermined set of values or by using a pair of oxygen sensors to determine the oxygen response delay across the sensors.

  20. Production of fructosyltransferase by Aureobasidium sp. ATCC 20524 in batch and two-step batch cultures.

    PubMed

    Salinas, Martín A; Perotti, Nora I

    2009-01-01

    A comparison of fructosyltransferase (EC 2.4.1.9) production by Aureobasidium sp. ATCC 20524 in batch and two step batch cultures was investigated in a 1-l stirred tank reactor using a sucrose supply of 200 g/l. Results showed that the innovative cultivation in two step of Aureobasidium sp. produced more fructosyltransferase (FFase) than the single batch culture at the same sucrose concentration with a maximal enzyme production of 523 U/ml, which was 80.5% higher than the one obtained in the batch culture. The production of fructooligosaccharides (FOSs) was also analyzed; their concentration reached a maximum value of 160 g/l the first day in the two-step culture and 127 g/l in the single-batch mode. The use of the two-step batch culture with Aureobasidium sp. ATCC 20524 in allowing the microorganism to grow up prior to the induction of sucrose (second step), proved to be a powerful method for producing fructosyltransferase and FOSs. PMID:18810518

  1. Batch and fed-batch fermentation of Bacillus thuringiensis using starch industry wastewater as fermentation substrate.

    PubMed

    Vu, Khanh Dang; Tyagi, Rajeshwar Dayal; Valéro, José R; Surampalli, Rao Y

    2010-08-01

    Bacillus thuringiensis var. kurstaki biopesticide was produced in batch and fed-batch fermentation modes using starch industry wastewater as sole substrate. Fed-batch fermentation with two intermittent feeds (at 10 and 20 h) during the fermentation of 72 h gave the maximum delta-endotoxin concentration (1,672.6 mg/L) and entomotoxicity (Tx) (18.5 x 10(6) SBU/mL) in fermented broth which were significantly higher than maximum delta-endotoxin concentration (511.0 mg/L) and Tx (15.8 x 10(6) SBU/mL) obtained in batch process. However, fed-batch fermentation with three intermittent feeds (at 10, 20 and 34 h) of the fermentation resulted in the formation of asporogenous variant (Spo-) from 36 h to the end of fermentation (72 h) which resulted in a significant decrease in spore and delta-endotoxin concentration and finally the Tx value. Tx of suspended pellets (27.4 x 10(6) SBU/mL) obtained in fed-batch fermentation with two feeds was the highest value as compared to other cases. PMID:19888605

  2. Uranium Adsorption on Ion-Exchange Resins - Batch Testing

    SciTech Connect

    Mattigod, Shas V.; Golovich, Elizabeth C.; Wellman, Dawn M.; Cordova, Elsa A.; Smith, Ronald M.

    2010-12-01

    The uranium adsorption performance of five resins (Dowex 1, Dowex 21K 16-30 [fresh], Dowex 21K 16-30 [regenerated], Purofine PFA600/4740, and ResinTech SIR-1200) were tested using unspiked, nitrate-spiked, and nitrate-spiked/pH adjusted source water from well 299-W19-36. These batch tests were conducted in support of a resin selection process in which the best resin to use for uranium treatment in the 200-West Area groundwater pump-and-treat system will be identified. The results from these tests are as follows: • The data from the high-nitrate (1331 mg/L) tests indicated that Dowex 1, Dowex 21K 16-30 (fresh), Purofine PFA600/4740, and ResinTech SIR-1200 all adsorbed uranium similarly well with Kd values ranging from ~15,000 to 95,000 ml/g. All four resins would be considered suitable for use in the treatment system based on uranium adsorption characteristics. • Lowering the pH of the high nitrate test conditions from 8.2 to 7.5 did not significantly change the uranium adsorption isotherms for the four tested resins. The Kd values for these four resins under high nitrate (1338 mg/L), lower pH (7.5) ranged from ~15,000 to 80,000 ml/g. • Higher nitrate concentrations greatly reduced the uranium adsorption on all four resins. Tests conducted with unspiked (no amendments; nitrate at 337 mg/L and pH at 8.2) source water yielded Kd values for Dowex 1, Dowex 21K 16-30 (fresh), Purofine PFA600/4740, and ResinTech SIR-1200 resins ranging from ~800,000 to >3,000,000 ml/g. These values are about two orders of magnitude higher than the Kd values noted from tests conducted using amended source water. • Compared to the fresh resin, the regenerated Dowex 21K 16-30 resin exhibited significantly lower uranium-adsorption performance under all test conditions. The calculated Kd values for the regenerated resin were typically an order of magnitude lower than the values calculated for the fresh resin. • Additional testing using laboratory columns is recommended to better

  3. Dimensionally Frustrated Diffusion towards Fractal Adsorbers

    NASA Astrophysics Data System (ADS)

    Nair, Pradeep R.; Alam, Muhammad A.

    2007-12-01

    Diffusion towards a fractal adsorber is a well-researched problem with many applications. While the steady-state flux towards such adsorbers is known to be characterized by the fractal dimension (DF) of the surface, the more general problem of time-dependent adsorption kinetics of fractal surfaces remains poorly understood. In this Letter, we show that the time-dependent flux to fractal adsorbers (1

  4. Standoff Spectroscopy of Surface Adsorbed Chemicals

    SciTech Connect

    Van Neste, Charles W; Senesac, Larry R; Thundat, Thomas George

    2009-01-01

    Despite its immediate applications, selective detection of trace quantities of surface adsorbed chemicals, such as explosives, without physically collecting the sample molecules is a challenging task. Standoff spectroscopic techniques offer an ideal method of detecting chemicals without using a sample collection step. Though standoff spectroscopic techniques are capable of providing high selectivity, their demonstrated sensitivities are poor. Here we describe standoff detection of trace quantities of surface adsorbed chemicals using two quantum cascade lasers operated simultaneously, with tunable wavelength windows that match with absorption peaks of the analytes. This standoff method is a variation of photoacoustic spectroscopy, where scattered light from the sample surface is used for exciting acoustic resonance of the detector. We demonstrate a sensitivity of 100 ng/cm{sup 2} and a standoff detection distance of 20 m for surface adsorbed analytes such as explosives and tributyl phosphate.

  5. Using Forensics to Untangle Batch Effects in TCGA Data - TCGA

    Cancer.gov

    Rehan Akbani, Ph.D., and colleagues at the University of Texas MD Anderson Cancer Center developed a tool called MBatch to detect, diagnose, and correct batch effects in TCGA data. Read more about batch effects in this Case Study.

  6. 21 CFR 80.38 - Treatment of batch after certification.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 1 2011-04-01 2011-04-01 false Treatment of batch after certification. 80.38... COLOR ADDITIVE CERTIFICATION Certification Procedures § 80.38 Treatment of batch after certification. (a... cosmetic....

  7. Ceria modified activated carbon: an efficient arsenic removal adsorbent for drinking water purification

    NASA Astrophysics Data System (ADS)

    Sawana, Radha; Somasundar, Yogesh; Iyer, Venkatesh Shankar; Baruwati, Babita

    2016-03-01

    Ceria (CeO2) coated powdered activated carbon was synthesized by a single step chemical process and demonstrated to be a highly efficient adsorbent for the removal of both As(III) and As(V) from water without any pre-oxidation process. The formation of CeO2 on the surface of powdered activated carbon was confirmed by X-ray diffraction, Raman spectroscopy and X-ray photoelectron spectroscopy. The percentage of Ce in the adsorbent was confirmed to be 3.5 % by ICP-OES. The maximum removal capacity for As(III) and As(V) was found to be 10.3 and 12.2 mg/g, respectively. These values are comparable to most of the commercially available adsorbents. 80 % of the removal process was completed within 15 min of contact time in a batch process. More than 95 % removal of both As(III) and As(V) was achieved within an hour. The efficiency of removal was not affected by change in pH (5-9), salinity, hardness, organic (1-4 ppm of humic acid) and inorganic anions (sulphate, nitrate, chloride, bicarbonate and fluoride) excluding phosphate. Presence of 100 ppm phosphate reduced the removal significantly from 90 to 18 %. The equilibrium adsorption pattern of both As(III) and As(V) fitted well with the Freundlich model with R 2 values 0.99 and 0.97, respectively. The material shows reusability greater than three times in a batch process (arsenic concentration reduced below 10 ppb from 330 ppb) and a life of at least 100 L in a column study with 80 g material when tested under natural hard water (TDS 1000 ppm, pH 7.8, hardness 600 ppm as CaCO3) spiked with 330 ppb of arsenic.

  8. Job Scheduling Under the Portable Batch System

    NASA Technical Reports Server (NTRS)

    Henderson, Robert L.; Woodrow, Thomas S. (Technical Monitor)

    1995-01-01

    The typical batch queuing system schedules jobs for execution by a set of queue controls. The controls determine from which queues jobs may be selected. Within the queue, jobs are ordered first-in, first-run. This limits the set of scheduling policies available to a site. The Portable Batch System removes this limitation by providing an external scheduling module. This separate program has full knowledge of the available queued jobs, running jobs, and system resource usage. Sites are able to implement any policy expressible in one of several procedural language. Policies may range from "bet fit" to "fair share" to purely political. Scheduling decisions can be made over the full set of jobs regardless of queue or order. The scheduling policy can be changed to fit a wide variety of computing environments and scheduling goals. This is demonstrated by the use of PBS on an IBM SP-2 system at NASA Ames.

  9. A New Dynamic Accumulator for Batch Updates

    NASA Astrophysics Data System (ADS)

    Wang, Peishun; Wang, Huaxiong; Pieprzyk, Josef

    A dynamic accumulator is an algorithm, which gathers together a large set of elements into a constant-size value such that for a given element accumulated, there is a witness confirming that the element was indeed included into the value, with a property that accumulated elements can be dynamically added and deleted into/from the original set such that the cost of an addition or deletion operation is independent of the number of accumulated elements. Although the first accumulator was presented ten years ago, there is still no standard formal definition of accumulators. In this paper, we generalize formal definitions for accumulators, formulate a security game for dynamic accumulators so-called Chosen Element Attack (CEA), and propose a new dynamic accumulator for batch updates based on the Paillier cryptosystem. Our construction makes a batch of update operations at unit cost. We prove its security under the extended strong RSA (es-RSA) assumption.

  10. Capacitated max -Batching with Interval Graph Compatibilities

    NASA Astrophysics Data System (ADS)

    Nonner, Tim

    We consider the problem of partitioning interval graphs into cliques of bounded size. Each interval has a weight, and the weight of a clique is the maximum weight of any interval in the clique. This natural graph problem can be interpreted as a batch scheduling problem. Solving a long-standing open problem, we show NP-hardness, even if the bound on the clique sizes is constant. Moreover, we give a PTAS based on a novel dynamic programming technique for this case.

  11. Analytical model of batch magnetophoretic separation

    NASA Astrophysics Data System (ADS)

    Kashevsky, S. B.; Kashevsky, B. E.

    2013-06-01

    Magnetophoresis (the motion of magnetic particles driven by the nonuniform magnetic field), that for a long time has been used for extracting magnetically susceptible objects in diverse industries, now attracts interest to develop more sophisticated microfluidic and batch techniques for separation and manipulation of biological particles, and magnetically assisted absorption and catalysis in organic chemistry, biochemistry, and petrochemistry. A deficiency of magnetic separation science is the lack of simple analytical models imitating real processes of magnetic separation. We have studied the motion of superparamagnetic (generally, soft magnetic) particles in liquid in the three-dimensional field of the diametrically polarized permanent cylindrical magnet; this geometry is basically representative of the batch separation mode. In the limit of the infinite-length magnet, we found the particle magnetophoresis proceeds independently of the magnet polarization direction, following the simple analytical relation incorporating all the relevant physical and geometrical parameters of the particle-magnet system. In experiments with a finite-length magnet we have shown applicability of the developed theory as to analyze the performance of the real batch separation systems in the noncooperative mode, and finally, we have presented an example of such analysis for the case of immunomagnetic cell separation and developed a criterion of the model limitation imposed by the magnetic aggregation of particles.

  12. EMISSIONS REDUCTION OF COMMERCIAL GLASSMAKING USING SELECTIVE BATCHING

    EPA Science Inventory

    The vertical bubble populations of selectively batched melts were compared to the vertical bubble populations of conventionally batched melts. “Conventional” refers to the use of a powdered batch. Bubble position and diameter measurements were taken on 24 crucibles...

  13. 40 CFR 63.1406 - Reactor batch process vent provisions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 12 2013-07-01 2013-07-01 false Reactor batch process vent provisions... Resins § 63.1406 Reactor batch process vent provisions. (a) Emission standards. Owners or operators of reactor batch process vents located at new or existing affected sources shall comply with paragraph...

  14. 40 CFR 63.1406 - Reactor batch process vent provisions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 12 2012-07-01 2011-07-01 true Reactor batch process vent provisions... § 63.1406 Reactor batch process vent provisions. (a) Emission standards. Owners or operators of reactor... reactor batch process vent located at a new affected source shall control organic HAP emissions...

  15. 40 CFR 63.1406 - Reactor batch process vent provisions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 11 2010-07-01 2010-07-01 true Reactor batch process vent provisions... § 63.1406 Reactor batch process vent provisions. (a) Emission standards. Owners or operators of reactor... reactor batch process vent located at a new affected source shall control organic HAP emissions...

  16. 40 CFR 63.1406 - Reactor batch process vent provisions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 11 2011-07-01 2011-07-01 false Reactor batch process vent provisions... § 63.1406 Reactor batch process vent provisions. (a) Emission standards. Owners or operators of reactor... reactor batch process vent located at a new affected source shall control organic HAP emissions...

  17. 40 CFR 63.1406 - Reactor batch process vent provisions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 12 2014-07-01 2014-07-01 false Reactor batch process vent provisions... Resins § 63.1406 Reactor batch process vent provisions. (a) Emission standards. Owners or operators of reactor batch process vents located at new or existing affected sources shall comply with paragraph...

  18. 40 CFR 63.462 - Batch cold cleaning machine standards.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 9 2011-07-01 2011-07-01 false Batch cold cleaning machine standards... National Emission Standards for Halogenated Solvent Cleaning § 63.462 Batch cold cleaning machine standards. (a) Each owner or operator of an immersion batch cold solvent cleaning machine shall comply with...

  19. 40 CFR 63.462 - Batch cold cleaning machine standards.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 10 2014-07-01 2014-07-01 false Batch cold cleaning machine standards... National Emission Standards for Halogenated Solvent Cleaning § 63.462 Batch cold cleaning machine standards. (a) Each owner or operator of an immersion batch cold solvent cleaning machine shall comply with...

  20. 40 CFR 63.462 - Batch cold cleaning machine standards.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 10 2013-07-01 2013-07-01 false Batch cold cleaning machine standards... National Emission Standards for Halogenated Solvent Cleaning § 63.462 Batch cold cleaning machine standards. (a) Each owner or operator of an immersion batch cold solvent cleaning machine shall comply with...

  1. 40 CFR 63.462 - Batch cold cleaning machine standards.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 10 2012-07-01 2012-07-01 false Batch cold cleaning machine standards... National Emission Standards for Halogenated Solvent Cleaning § 63.462 Batch cold cleaning machine standards. (a) Each owner or operator of an immersion batch cold solvent cleaning machine shall comply with...

  2. 7 CFR 58.728 - Cooking the batch.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 3 2013-01-01 2013-01-01 false Cooking the batch. 58.728 Section 58.728 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Standards... Procedures § 58.728 Cooking the batch. Each batch of cheese within the cooker, including the...

  3. 7 CFR 58.728 - Cooking the batch.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 3 2012-01-01 2012-01-01 false Cooking the batch. 58.728 Section 58.728 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Standards... Procedures § 58.728 Cooking the batch. Each batch of cheese within the cooker, including the...

  4. 7 CFR 58.728 - Cooking the batch.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 3 2011-01-01 2011-01-01 false Cooking the batch. 58.728 Section 58.728 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Standards... Procedures § 58.728 Cooking the batch. Each batch of cheese within the cooker, including the...

  5. 7 CFR 58.728 - Cooking the batch.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 3 2014-01-01 2014-01-01 false Cooking the batch. 58.728 Section 58.728 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Standards... Procedures § 58.728 Cooking the batch. Each batch of cheese within the cooker, including the...

  6. 40 CFR 63.462 - Batch cold cleaning machine standards.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 9 2010-07-01 2010-07-01 false Batch cold cleaning machine standards... National Emission Standards for Halogenated Solvent Cleaning § 63.462 Batch cold cleaning machine standards. (a) Each owner or operator of an immersion batch cold solvent cleaning machine shall comply with...

  7. 21 CFR 80.38 - Treatment of batch after certification.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Treatment of batch after certification. 80.38... COLOR ADDITIVE CERTIFICATION Certification Procedures § 80.38 Treatment of batch after certification. (a) Immediately upon notification that a batch of color additive has been certified, the person...

  8. 21 CFR 80.37 - Treatment of batch pending certification.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Treatment of batch pending certification. 80.37... COLOR ADDITIVE CERTIFICATION Certification Procedures § 80.37 Treatment of batch pending certification. Immediately after the sample that is to accompany a request for certification of a batch of color additive...

  9. 40 CFR 63.1321 - Batch process vents provisions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 11 2010-07-01 2010-07-01 true Batch process vents provisions. 63.1321... Standards for Hazardous Air Pollutant Emissions: Group IV Polymers and Resins § 63.1321 Batch process vents provisions. (a) Batch process vents. Except as specified in paragraphs (b) through (d) of this...

  10. A Semi-Batch Reactor Experiment for the Undergraduate Laboratory

    ERIC Educational Resources Information Center

    Derevjanik, Mario; Badri, Solmaz; Barat, Robert

    2011-01-01

    This experiment and analysis offer an economic yet challenging semi-batch reactor experience. Household bleach is pumped at a controlled rate into a batch reactor containing pharmaceutical hydrogen peroxide solution. Batch temperature, product molecular oxygen, and the overall change in solution conductivity are metered. The reactor simulation…

  11. Removal of aqueous nickel (II) using laterite as a low-cost adsorbent.

    PubMed

    Mukherjee, Somnath; Kumar, Sunil; Misra, A K; Acharya, P C

    2006-10-01

    The present paper describes the laboratory study of laterite as a low-cost adsorbent for removal of aqueous nickel (II). At pH 7 and a temperature of 30 degrees C, a sorbent dose of 15 mg/L resulted in approximately 90% removal of nickel (II) from its initial concentration of 10 mg/L. A maximum removal of 98% of the adsorbate was observed with an adsorbent particle size of 210 micro with the above conditions. Batch kinetics results were described by fitting in a Langmuir isotherm. Helffrich's half-time equation (Helffrich, 1962) has been applied to evaluate the adsorption process. It appears that film diffusion would be the rate-limiting step. The effect of pH on the sorption process was carried out to a value of 8.0. The removal rate of nickel was found to be the function of pH of the reaction mixture. The rate of nickel uptake by laterite with the decrease in pH value has been explained on the basis of aqueous-complex formation and the subsequent acid-base dissociation at the solid-solution interface. PMID:17120446

  12. Adsorption and removal kinetics of phosphonate from water using natural adsorbents.

    PubMed

    Kumar, R Anil; Velayudhan, K T; Ramachandran, V; Bhai, R Susheela; Unnikrishnan, G; Vasu, K

    2010-01-01

    The removal of phosphonate from water was studied using some natural adsorbents. Potassium phosphonate is a fungicide used for the control of Phytophthora capsici, which is prevalent in black pepper (Piper nigrum L.). Batch adsorption kinetic experiments were conducted on the adsorption of phosphonate onto the adsorbents. The concentration of phosphonate was measured on a high-performance liquid chromatograph fitted with a conductivity detector. The percentage removal of phosphonate by powdered laterite stone (PLS) from water was 40.4%, within a residence time of 15 minutes. The mechanisms of the rate of adsorption were analyzed and compared using the pseudo-second-order, Elovich, and intraparticle diffusion models. The experimental data was found to correlate well with the pseudo-second-order kinetic model, indicating adsorption as a chemisorption process. A possible reaction in the phosphonate-PLS system also has been proposed. The PLS can be used as a low-cost natural adsorbent for phosphonate removal from water. PMID:20112539

  13. Food-processes wastewaters treatment using food solid-waste materials as adsorbents or absorbents

    NASA Astrophysics Data System (ADS)

    Rapti, Ilaira; Georgopoulos, Stavros; Antonopoulou, Maria; Konstantinou, Ioannis; Papadaki, Maria

    2016-04-01

    The wastewaters generated by olive-mills during the production of olive oil, wastewaters from a dairy and a cow-farm unit and wastewaters from a small food factory have been treated by means of selected materials, either by-products of the same units, or other solid waste, as absorbents or adsorbents in order to identify the capacity of those materials to remove organic load and toxicity from the aforementioned wastewaters. The potential of both the materials used as absorbents as well as the treated wastewaters to be further used either as fertilizers or for agricultural irrigation purposes are examined. Dry olive leaves, sheep wool, rice husks, etc. were used either in a fixed-bed or in a stirred batch arrangemen,t employing different initial concentrations of the aforementioned wastewaters. The efficiency of removal was assessed using scpectrophotometric methods and allium test phytotoxicity measurements. In this presentation the response of each material employed is shown as a function of absorbent/adsorbent quantity and kind, treatment time and wastewater kind and initial organic load. Preliminary results on the potential uses of the adsorbents/absorbents and the treated wastewaters are also shown. Keywords: Olive-mill wastewaters, dairy farm wastewaters, olive leaves, zeolite, sheep wool

  14. Semiautomated, Reproducible Batch Processing of Soy

    NASA Technical Reports Server (NTRS)

    Thoerne, Mary; Byford, Ivan W.; Chastain, Jack W.; Swango, Beverly E.

    2005-01-01

    A computer-controlled apparatus processes batches of soybeans into one or more of a variety of food products, under conditions that can be chosen by the user and reproduced from batch to batch. Examples of products include soy milk, tofu, okara (an insoluble protein and fiber byproduct of soy milk), and whey. Most processing steps take place without intervention by the user. This apparatus was developed for use in research on processing of soy. It is also a prototype of other soy-processing apparatuses for research, industrial, and home use. Prior soy-processing equipment includes household devices that automatically produce soy milk but do not automatically produce tofu. The designs of prior soy-processing equipment require users to manually transfer intermediate solid soy products and to press them manually and, hence, under conditions that are not consistent from batch to batch. Prior designs do not afford choices of processing conditions: Users cannot use previously developed soy-processing equipment to investigate the effects of variations of techniques used to produce soy milk (e.g., cold grinding, hot grinding, and pre-cook blanching) and of such process parameters as cooking times and temperatures, grinding times, soaking times and temperatures, rinsing conditions, and sizes of particles generated by grinding. In contrast, the present apparatus is amenable to such investigations. The apparatus (see figure) includes a processing tank and a jacketed holding or coagulation tank. The processing tank can be capped by either of two different heads and can contain either of two different insertable mesh baskets. The first head includes a grinding blade and heating elements. The second head includes an automated press piston. One mesh basket, designated the okara basket, has oblong holes with a size equivalent to about 40 mesh [40 openings per inch (.16 openings per centimeter)]. The second mesh basket, designated the tofu basket, has holes of 70 mesh [70 openings

  15. The biogeochemical cycle of the adsorbed template. II - Selective adsorption of mononucleotides on adsorbed polynucleotide templates

    NASA Technical Reports Server (NTRS)

    Lazard, Daniel; Lahav, Noam; Orenberg, James B.

    1988-01-01

    Experimental results are presented for the verification of the specific interaction step of the 'adsorbed template' biogeochemical cycle, a simple model for a primitive prebiotic replication system. The experimental system consisted of gypsum as the mineral to which an oligonucleotide template attaches (Poly-C or Poly-U) and (5-prime)-AMP, (5-prime)-GMP, (5-prime)-CMP and (5-prime)-UMP as the interacting biomonomers. When Poly-C or Poly-U were used as adsorbed templates, (5-prime)-GMP and (5-prime)-AMP, respectively, were observed to be the most strongly adsorbed species.

  16. Blue Ribbon Panel Report - BRP - Cancer Moonshot

    Cancer.gov

    The Blue Ribbon Panel Report outlines 10 recommendations to accelerate progress against cancer. The panel was established to ensure that the Cancer Moonshot's approaches are grounded in the best science.

  17. Unoccupied electronic states in adsorbate systems

    NASA Astrophysics Data System (ADS)

    Bertel, E.

    1991-11-01

    Experimental work on unoccupied electronic states in adsorbate systems on metallic substrates is reviewed with emphasis on recent developments. The first part is devoted to molecular adsorbates. Weakly chemisorbed hydrocarbons are briefly discussed. An exhaustive inverse photoemission (IPE) study of the CO bond to the transition metals Ni, Pb, and Pt is presented. Adsorbed NO is taken as an example to demonstrate the persisting discrepancies in the interpretation of IPE spectra. Atomic adsorbates are discussed in the second part. The quantum well state model is applied to interpret the surface states in reconstructing and non-reconstructing adsorption systems of alkali metals and hydrogen. A recent controversy on the unoccupied electronic states of the Cu(110)/O p(2×1) surface is critically reviewed. The quantum well state model is then compared to tight binding and local-density-functional calculations of the unoccupied bands and the deficiencies of the various approaches are pointed out. Finally, the relation between the surface state model and more chemically oriented models of surface bonding is briefly discussed.

  18. SLUDGE BATCH 5 SIMULANT FLOWSHEET STUDIES

    SciTech Connect

    Lambert, D; Michael Stone, M; Bradley Pickenheim, B; David Best, D; David Koopman, D

    2008-10-03

    The Defense Waste Processing Facility (DWPF) will transition from Sludge Batch 4 (SB4) processing to Sludge Batch 5 (SB5) processing in early fiscal year 2009. Tests were conducted using non-radioactive simulants of the expected SB5 composition to determine the impact of varying the acid stoichiometry during the Sludge Receipt and Adjustment Tank (SRAT) and Slurry Mix Evaporator (SME) processes. The work was conducted to meet the Technical Task Request (TTR) HLW/DWPF/TTR-2007-0007, Rev. 1 and followed the guidelines of a Task Technical and Quality Assurance Plan (TT&QAP). The flowsheet studies are performed to evaluate the potential chemical processing issues, hydrogen generation rates, and process slurry rheological properties as a function of acid stoichiometry. Initial SB5 flowsheet studies were conducted to guide decisions during the sludge batch preparation process. These studies were conducted with the estimated SB5 composition at the time of the study. The composition has changed slightly since these studies were completed due to changes in the washing plan to prepare SB5 and the estimated SB4 heel mass. Nine DWPF process simulations were completed in 4-L laboratory-scale equipment using both a batch simulant (Tank 51 simulant after washing is complete) and a blend simulant (Tank 40 simulant after Tank 51 transfer is complete). Each simulant had a set of four SRAT and SME simulations at varying acid stoichiometry levels (115%, 130%, 145% and 160%). One additional run was made using blend simulant at 130% acid that included additions of the Actinide Removal Process (ARP) waste prior to acid addition and the Modular Caustic Side Solvent Extraction (CSSX) Unit (MCU) waste following SRAT dewatering. There are several parameters that are noteworthy concerning SB5 sludge: (1) This is the first batch DWPF will be processing that contains sludge that has had a significant fraction of aluminum removed through aluminum dissolution. (2) The sludge is high in mercury

  19. BATCH-GE: Batch analysis of Next-Generation Sequencing data for genome editing assessment

    PubMed Central

    Boel, Annekatrien; Steyaert, Woutert; De Rocker, Nina; Menten, Björn; Callewaert, Bert; De Paepe, Anne; Coucke, Paul; Willaert, Andy

    2016-01-01

    Targeted mutagenesis by the CRISPR/Cas9 system is currently revolutionizing genetics. The ease of this technique has enabled genome engineering in-vitro and in a range of model organisms and has pushed experimental dimensions to unprecedented proportions. Due to its tremendous progress in terms of speed, read length, throughput and cost, Next-Generation Sequencing (NGS) has been increasingly used for the analysis of CRISPR/Cas9 genome editing experiments. However, the current tools for genome editing assessment lack flexibility and fall short in the analysis of large amounts of NGS data. Therefore, we designed BATCH-GE, an easy-to-use bioinformatics tool for batch analysis of NGS-generated genome editing data, available from https://github.com/WouterSteyaert/BATCH-GE.git. BATCH-GE detects and reports indel mutations and other precise genome editing events and calculates the corresponding mutagenesis efficiencies for a large number of samples in parallel. Furthermore, this new tool provides flexibility by allowing the user to adapt a number of input variables. The performance of BATCH-GE was evaluated in two genome editing experiments, aiming to generate knock-out and knock-in zebrafish mutants. This tool will not only contribute to the evaluation of CRISPR/Cas9-based experiments, but will be of use in any genome editing experiment and has the ability to analyze data from every organism with a sequenced genome. PMID:27461955

  20. BATCH-GE: Batch analysis of Next-Generation Sequencing data for genome editing assessment.

    PubMed

    Boel, Annekatrien; Steyaert, Woutert; De Rocker, Nina; Menten, Björn; Callewaert, Bert; De Paepe, Anne; Coucke, Paul; Willaert, Andy

    2016-01-01

    Targeted mutagenesis by the CRISPR/Cas9 system is currently revolutionizing genetics. The ease of this technique has enabled genome engineering in-vitro and in a range of model organisms and has pushed experimental dimensions to unprecedented proportions. Due to its tremendous progress in terms of speed, read length, throughput and cost, Next-Generation Sequencing (NGS) has been increasingly used for the analysis of CRISPR/Cas9 genome editing experiments. However, the current tools for genome editing assessment lack flexibility and fall short in the analysis of large amounts of NGS data. Therefore, we designed BATCH-GE, an easy-to-use bioinformatics tool for batch analysis of NGS-generated genome editing data, available from https://github.com/WouterSteyaert/BATCH-GE.git. BATCH-GE detects and reports indel mutations and other precise genome editing events and calculates the corresponding mutagenesis efficiencies for a large number of samples in parallel. Furthermore, this new tool provides flexibility by allowing the user to adapt a number of input variables. The performance of BATCH-GE was evaluated in two genome editing experiments, aiming to generate knock-out and knock-in zebrafish mutants. This tool will not only contribute to the evaluation of CRISPR/Cas9-based experiments, but will be of use in any genome editing experiment and has the ability to analyze data from every organism with a sequenced genome. PMID:27461955

  1. Development and Testing of Molecular Adsorber Coatings

    NASA Technical Reports Server (NTRS)

    Abraham, Nithin; Hasegawa, Mark; Straka, Sharon

    2012-01-01

    The effect of on-orbit molecular contamination has the potential to degrade the performance of spaceflight hardware and diminish the lifetime of the spacecraft. For example, sensitive surfaces, such as optical surfaces, electronics, detectors, and thermal control surfaces, are vulnerable to the damaging effects of contamination from outgassed materials. The current solution to protect these surfaces is through the use of zeolite coated ceramic adsorber pucks. However, these pucks and its additional complex mounting hardware requirements result in several disadvantages, such as size, weight, and cost related concerns, that impact the spacecraft design and the integration and test schedule. As a result, a new innovative molecular adsorber coating was developed as a sprayable alternative to mitigate the risk of on-orbit molecular contamination. In this study, the formulation for molecular adsorber coatings was optimized using various binders, pigment treatment methods, binder to pigment ratios, thicknesses, and spray application techniques. The formulations that passed coating adhesion and vacuum thermal cycling tests were further tested for its adsorptive capacity. Accelerated molecular capacitance tests were performed in an innovatively designed multi-unit system containing idealized contaminant sources. This novel system significantly increased the productivity of the testing phase for the various formulations that were developed. Work performed during the development and testing phases has demonstrated successful application of molecular adsorber coatings onto metallic substrates, as well as, very promising results for the adhesion performance and the molecular capacitance of the coating. Continued testing will assist in the qualification of molecular adsorber coatings for use on future contamination sensitive spaceflight missions.

  2. Coalesced chitosan activated carbon composite for batch and fixed-bed adsorption of cationic and anionic dyes.

    PubMed

    Auta, M; Hameed, B H

    2013-05-01

    A renewable waste tea activated carbon (WTAC) was coalesced with chitosan to form composite adsorbent used for waste water treatment. Adsorptive capacities of crosslinked chitosan beads (CCB) and its composite (WTAC-CCB) for Methylene blue dye (MB) and Acid blue 29 (AB29) were evaluated through batch and fixed-bed studies. Langmuir, Freundlich and Temkin adsorption isotherms were tested for the adsorption process and the experimental data were best fitted by Langmuir model and least by Freundlich model; the suitability of fitness was adjudged by the Chi-square (χ(2)) and Marquadt's percent standard deviation error functions. Judging by the values of χ(2), pseudo-second-order reaction model best described the adsorption process than pseudo-first-order kinetic model for MB/AB29 on both adsorbents. After five cycles of adsorbents desorption test, more than 50% WTAC-CCB adsorption efficiency was retained while CCB had <20% adsorption efficiency. The results of this study revealed that WTAC-CCB composite is a promising adsorbent for treatment of anionic and cationic dyes in effluent wastewaters. PMID:23376092

  3. Natural Transformation of Azotobacter vinelandii by Adsorbed Chromosomal DNA: Role of Adsorbed DNA Conformation

    NASA Astrophysics Data System (ADS)

    Lv, N.; Zilles, J.; Nguyen, H.

    2008-12-01

    Recent increases in antibiotic resistance among pathogenic microorganisms and the accompanying public health concerns result both from the widespread use of antibiotics and from the transfer of antibiotic resistance genes among microorganisms. To understand the transfer of antibiotic resistance genes and identify efficient measures to minimize these transfers, an interdisciplinary approach was used to identify physical and chemical factors that control the fate and biological availability of extracellular DNA. Quartz crystal microbalance with dissipation (QCM-D) was used to study extracellular DNA adsorption and the conformation of the adsorbed DNA on silica and natural organic matter (NOM) surfaces. Solution chemistry was varied systematically to investigate the role of adsorbed DNA conformation on transformation. Gene transfer was assessed under the same conditions using natural transformation of chromosomal DNA into the soil bacteria Azotobacter vinelandii. DNA adsorbed to both silica and NOM surfaces has a more compact and rigid conformation in the presence of Ca2+ compared to Na+. Extracellular DNA adsorbed on silica and NOM surfaces transformed A. vinelandii. The transformation efficiency of adsorbed DNA was up to 4 orders of magnitude lower than that of dissolved DNA. Preliminary results suggest that the presence of Ca2+ in groundwater (e.g. hardness) reduces the availability of adsorbed DNA for transformation.

  4. Magnesium oxide-impregnated tuff soil-derived ceramic: a novel cadmium(II) adsorbing media

    NASA Astrophysics Data System (ADS)

    Salim, Md; Bhakta, Jatindra N.; Maneesh, Namburath; Munekage, Yukihiro; Motomura, Kevin

    2015-07-01

    The contamination of cadmium (Cd) in the aquatic environment is one of the serious environmental and human health's risks. The present study attempted to develop the potential magnesium oxide (MgO)-impregnated tuff soil-derived ceramic (MITDC)-based novel adsorbent media for adsorbing higher rate of cadmium [Cd(II)] from water phase. A potential MITDC adsorbent media was developed using volcanic raw tuff soil and its Cd(II) adsorption capacity from water phase was evaluated comparing with the raw tuff soil. A series of studies were carried out in an agitated batch method at 20 ± 2 °C to characterize the adsorption capacity of MITDC under different conditions of factors, such as contact time (0-360 min), initial pH (3-11) of solution, dose of MITDC (2, 5, 7.5 and 10 g/L), and initial concentration of Cd(II) (5, 10, 20, 30, and 40 mg/L), influencing the adsorption mechanism. MITDC exhibited the equilibrium state of maximum Cd(II) adsorption at the contact time 120 min and pH 4.7 (removed 98.2 % Cd) when initial Cd(II) concentration was 10 mg/L in the present study. The dose of 7.5 g MITDC/L showed maximum removal of Cd(II) from water. Experimental data were described by the Freundlich and the Langmuir isotherms and equilibrium data fitted well with the Langmuir model (R 2 = 0.996). The Cd(II) adsorption capacity of MITDC was 31.25 mg/g. The high Cd(II) adsorption capacity indicated that novel MITDC could be used as a potential ceramic adsorbent media to remove high rate of Cd(II) from aqueous phase.

  5. Removing adsorbed heavy metal ions from sand surfaces via applying interfacial properties of rhamnolipid.

    PubMed

    Haryanto, Bode; Chang, Chien-Hsiang

    2015-01-01

    In this study, the interfacial properties of biosurfactant rhamnolipid were investigated and were applied to remove adsorbed heavy metal ions from sand surfaces with flushing operations. The surface tension-lowering activity, micelle charge characteristic, and foaming ability of rhamnolipid were identified first. For rhamnolipid in water, the negatively charged characteristic of micelles or aggregates was confirmed and the foaming ability at concentrations higher than 40 mg/L was evaluated. By using the rhamnolipid solutions in a batch washing approach, the potential of applying the interfacial properties of rhamnolipid to remove adsorbed copper ions from sand surfaces was then demonstrated. In rhamnolipid solution flushing operations for sand-packed medium, higher efficiency was found for the removal of adsorbed copper ions with residual type than with inner-sphere interaction type, implying the important role of interaction type between the copper ion and the sand surface in the removal efficiency. In addition, the channeling effect of rhamnolipid solution flow in the sand-packed medium was clearly observed in the solution flushing operations and was responsible for the low removal efficiency with low contact areas between solution and sand. By using rhamnolipid solution with foam to flush the sand-packed medium, one could find that the channeling effect of the solution flow was reduced and became less pronounced with the increase in the rhamnolipid concentration, or with the enhanced foaming ability. With the reduced channeling effect in the flushing operations, the removal efficiency for adsorbed copper ions was significantly improved. The results suggested that the foam-enhanced rhamnolipid solution flushing operation was efficient in terms of surfactant usage and operation time. PMID:25748376

  6. Batch and continuous recrystallization of secondary explosives

    SciTech Connect

    Moodie, W.J.; Bennett, J.E.

    1984-03-09

    Explosive powders are recrystallized at Mound for use in development and production programs of the US Department of Energy. Batch and continuous precipitation units are operated on a small scale to produce powders of different crystal morphology over a wide range of specific surface areas. The equipment and procedures are described for both methods of operation. Safety aspects, and features designed to optimize product purity and freedom from contamination, are discussed. Experimental studies are conducted to determine the effects of varying the process parameters. The results are used to select the operating conditions to make powders for specific applications.

  7. Characterization of Three LYSO Crystal Batches

    NASA Astrophysics Data System (ADS)

    Yang, Fan; Mao, Rihua; Zhang, Liyuan; Zhu, Ren-Yuan

    2015-02-01

    We report on three LYSO crystal batches characterized at the Caltech crystal laboratory for future HEP experiments: Twenty-five 20 cm long crystals for the SuperB experiment; twelve 13 cm long crystals for the Mu2e experiment and 623 14×14×1.5 mm plates with five holes for a LYSO/W Shashlik matrix for a beam test at Fermilab. Optical and scintillation properties measured are longitudinal Transmittance, light output and FWHM energy resolution. Correlations between these properties are also investigated.

  8. Characterization of three LYSO crystal batches

    NASA Astrophysics Data System (ADS)

    Yang, Fan; Mao, Rihua; Zhang, Liyuan; Zhu, Ren-Yuan

    2015-06-01

    We report on three LYSO crystal batches characterized at the Caltech crystal laboratory for future HEP experiments: 25 20 cm long crystals for the SuperB experiment; 12 13 cm long crystals for the Mu2e experiment and 623 14×14×1.5 mm3 plates with five holes for a LYSO/W Shashlik matrix for a beam test at Fermilab. Optical and scintillation properties measured are longitudinal transmittance, light output and FWHM energy resolution. Correlations between these properties are also investigated.

  9. Chloro-Organics in Papermill Effluent: Identification and Removal by Sequencing Batch Biofilm Reactor

    NASA Astrophysics Data System (ADS)

    Abd. Rahman, Rakmi; Zahrim, A. Y.; Abu Bakar, Azizah

    Effluents from paper mills are among major sources of aquatic pollution and may be toxic since they contain chlorinated phenolic compounds which are measured as adsorbable organic halides (AOX). In this work, removal of chlorophenol was investigated using a Sequencing Batch Biofilm Reactor (SBBR) with Granular Activated Carbon (GAC) as a growth media. Wastewater for this study was obtained from treated effluent outlet of a papermill in Selangor. Treatment of the papermill secondary effluent shows that SBBR process, with a combination of adsorption and biodegradation, gave a good removal of pentachlorophenol (PCP), on average, about 70%. The growth kinetic parameters obtained were: YH = 0.6504 mg biomass/mg PCP, dH = 6.50x10-5 h-1, μh = 0.00315 h-1 and Ks = 5.82 mg PCP L-1. These show that the SBBR system is suitable to be operated at long SRTs.

  10. In-line image analysis on the effects of additives in batch cooling crystallization

    NASA Astrophysics Data System (ADS)

    Qu, Haiyan; Louhi-Kultanen, Marjatta; Kallas, Juha

    2006-03-01

    The effects of two potassium salt additives, ethylene diamine tetra acetic acid dipotassium salt (EDTA) and potassium pyrophosphate (KPY), on the batch cooling crystallization of potassium dihydrogen phosphate (KDP) were investigated. The crystal growth rates of certain crystal faces were determined from in-line images taken with a MTS particle image analysis (PIA) video microscope. An in-line image processing method was developed to characterize the size and shape of the crystals. The nucleation kinetics was studied by measurement of the metastable zone width and induction time. A significant promotion effect on both nucleation and growth of KDP was observed when EDTA was used as an additive. KPY, however, exhibited strong inhibiting impacts. The mechanism underlying the EDTA promotion effect on crystal growth was further studied with the 2-dimension nucleation model. It is shown that the presence of EDTA increased the density of adsorbed molecules of the crystallizing solute on the surface of the crystal.

  11. EMERGING TECHNOLOGY SUMMARY: DEMONSTRATION OF AMBERSORB 563 ADSORBENT TECHNOLOGY

    EPA Science Inventory

    A field pilot study was conducted to demonstrate the technical feasibility and cost-effectiveness of Ambersorb® 5631 carbonaceous adsorbent for remediating groundwater contaminated with volatile organic compounds (VOCs). The Ambersorb adsorbent technology demonstration consist...

  12. A novel magnetic adsorbent based on waste litchi peels for removing Pb(II) from aqueous solution.

    PubMed

    Jiang, Ruixue; Tian, Jiyu; Zheng, Hao; Qi, Jinqiu; Sun, Shujuan; Li, Xiaochen

    2015-05-15

    A new magnetic bioadsorbent, magnetic litchi peel (MLP), was synthesized by coating powdered litchi peel with Fe3O4, and was used for removing Pb(II) from aqueous solutions. The influencing factors, adsorption isotherms, kinetics, and thermodynamics of Pb(II) adsorption by MLP were investigated using batch assays. Optimum Pb(II) adsorption by MLP was achieved using a contact time of 120 min, an adsorbent dose of 5 g/L, and pH of 6.0. The adsorption equilibrium data conformed to the Langmuir isotherm model, yielding a maximum Pb(II) adsorption capacity of 78.74 mg/g. The adsorption kinetics for Pb(II) adsorption by MLP followed a pseudo-second-order model. The thermodynamic results suggested that Pb(II) adsorption by MLP was spontaneous and exothermic. Additionally, the magnetic adsorbent was easily and rapidly separated out of solution under an external magnetic field. PMID:25770959

  13. Polymer composite adsorbents using particles of molecularly imprinted polymers or aluminium oxide nanoparticles for treatment of arsenic contaminated waters.

    PubMed

    Önnby, L; Pakade, V; Mattiasson, B; Kirsebom, H

    2012-09-01

    Removal of As(V) by adsorption from water solutions was studied using three different synthetic adsorbents. The adsorbents, (a) aluminium nanoparticles (Alu-NPs, <50 nm) incorporated in amine rich cryogels (Alu-cryo), (b) molecular imprinted polymers (<38 μm) in polyacrylamide cryogels (MIP-cryo) and (c) thiol functionalised cryogels (SH-cryo) were evaluated regarding material characteristics and arsenic removal in batch test and continuous mode. Results revealed that a composite design with particles incorporated in cryogels was a successful means for applying small particles (nano- and micro- scale) in water solutions with maintained adsorption capacity and kinetics. Low capacity was obtained from SH-cryo and this adsorbent was hence excluded from the study. The adsorption capacities for the composites were 20.3 ± 0.8 mg/g adsorbent (Alu-cryo) and 7.9 ± 0.7 mg/g adsorbent (MIP-cryo) respectively. From SEM images it was seen that particles were homogeneously distributed in Alu-cryo and heterogeneously distributed in MIP-cryo. The particle incorporation increased the mechanical stability and the polymer backbones of pure polyacrylamide (MIP-cryo) were of better stability than the amine containing polymer backbone (Alu-cryo). Both composites worked well in the studied pH range of pH 2-8. Adsorption tested in real wastewater spiked with arsenic showed that co-ions (nitrate, sulphate and phosphate) affected arsenic removal for Alu-cryo more than for MIP-cryo. Both composites still adsorbed well in the presence of counter-ions (copper and zinc) present at low concentrations (μg/l). The unchanged and selective adsorption in realistic water observed for MIP-cryo was concluded to be due to a successful imprinting, here controlled using a non-imprinted polymer (NIP). A development of MIP-cryo is needed, considering its low adsorption capacity. PMID:22687522

  14. Analysis of Adsorbed Natural Gas Tank Technology

    NASA Astrophysics Data System (ADS)

    Knight, Ernest; Schultz, Conrad; Rash, Tyler; Dohnke, Elmar; Stalla, David; Gillespie, Andrew; Sweany, Mark; Seydel, Florian; Pfeifer, Peter

    With gasoline being an ever decreasing finite resource and with the desire to reduce humanity's carbon footprint, there has been an increasing focus on innovation of alternative fuel sources. Natural gas burns cleaner, is more abundant, and conforms to modern engines. However, storing compressed natural gas (CNG) requires large, heavy gas cylinders, which limits space and fuel efficiency. Adsorbed natural gas (ANG) technology allows for much greater fuel storage capacity and the ability to store the gas at a much lower pressure. Thus, ANG tanks are much more flexible in terms of their size, shape, and weight. Our ANG tank employs monolithic nanoporous activated carbon as its adsorbent material. Several different configurations of this Flat Panel Tank Assembly (FPTA) along with a Fuel Extraction System (FES) were examined to compare with the mass flow rate demands of an engine.

  15. Gas storage using fullerene based adsorbents

    NASA Technical Reports Server (NTRS)

    Loutfy, Raouf O. (Inventor); Lu, Xiao-Chun (Inventor); Li, Weijiong (Inventor); Mikhael, Michael G. (Inventor)

    2000-01-01

    This invention is directed to the synthesis of high bulk density high gas absorption capacity adsorbents for gas storage applications. Specifically, this invention is concerned with novel gas absorbents with high gravimetric and volumetric gas adsorption capacities which are made from fullerene-based materials. By pressing fullerene powder into pellet form using a conventional press, then polymerizing it by subjecting the fullerene to high temperature and high inert gas pressure, the resulting fullerene-based materials have high bulk densities and high gas adsorption capacities. By pre-chemical modification or post-polymerization activation processes, the gas adsorption capacities of the fullerene-based adsorbents can be further enhanced. These materials are suitable for low pressure gas storage applications, such as oxygen storage for home oxygen therapy uses or on-board vehicle natural gas storage. They are also suitable for storing gases and vapors such as hydrogen, nitrogen, carbon dioxide, and water vapor.

  16. Computer simulations of adsorbed liquid crystal films

    NASA Astrophysics Data System (ADS)

    Wall, Greg D.; Cleaver, Douglas J.

    2003-01-01

    The structures adopted by adsorbed thin films of Gay-Berne particles in the presence of a coexisting vapour phase are investigated by molecular dynamics simulation. The films are adsorbed at a flat substrate which favours planar anchoring, whereas the nematic-vapour interface favours normal alignment. On cooling, a system with a high molecule-substrate interaction strength exhibits substrate-induced planar orientational ordering and considerable stratification is observed in the density profiles. In contrast, a system with weak molecule-substrate coupling adopts a director orientation orthogonal to the substrate plane, owing to the increased influence of the nematic-vapour interface. There are significant differences between the structures adopted at the two interfaces, in contrast with the predictions of density functional treatments of such systems.

  17. Medication Waste Reduction in Pediatric Pharmacy Batch Processes

    PubMed Central

    Veltri, Michael A.; Hamrock, Eric; Mollenkopf, Nicole L.; Holt, Kristen; Levin, Scott

    2014-01-01

    OBJECTIVES: To inform pediatric cart-fill batch scheduling for reductions in pharmaceutical waste using a case study and simulation analysis. METHODS: A pre and post intervention and simulation analysis was conducted during 3 months at a 205-bed children's center. An algorithm was developed to detect wasted medication based on time-stamped computerized provider order entry information. The algorithm was used to quantify pharmaceutical waste and associated costs for both preintervention (1 batch per day) and postintervention (3 batches per day) schedules. Further, simulation was used to systematically test 108 batch schedules outlining general characteristics that have an impact on the likelihood for waste. RESULTS: Switching from a 1-batch-per-day to a 3-batch-per-day schedule resulted in a 31.3% decrease in pharmaceutical waste (28.7% to 19.7%) and annual cost savings of $183,380. Simulation results demonstrate how increasing batch frequency facilitates a more just-in-time process that reduces waste. The most substantial gains are realized by shifting from a schedule of 1 batch per day to at least 2 batches per day. The simulation exhibits how waste reduction is also achievable by avoiding batch preparation during daily time periods where medication administration or medication discontinuations are frequent. Last, the simulation was used to show how reducing batch preparation time per batch provides some, albeit minimal, opportunity to decrease waste. CONCLUSIONS: The case study and simulation analysis demonstrate characteristics of batch scheduling that may support pediatric pharmacy managers in redesign toward minimizing pharmaceutical waste. PMID:25024671

  18. Remediation of Organic and Inorganic Arsenic Contaminated Groundwater using a Nonocrystalline TiO2 Based Adsorbent

    SciTech Connect

    Jing, C.; Meng, X; Calvache, E; Jiang, G

    2009-01-01

    A nanocrystalline TiO2-based adsorbent was evaluated for the simultaneous removal of As(V), As(III), monomethylarsonic acid (MMA), and dimethylarsinic acid (DMA) in contaminated groundwater. Batch experimental results show that As adsorption followed pseudo-second order rate kinetics. The competitive adsorption was described with the charge distribution multi-site surface complexation model (CD-MUSIC). The groundwater containing an average of 329 ?g L-1 As(III), 246 ?g L-1 As(V), 151 ?g L-1 MMA, and 202 ?g L-1 DMA was continuously passed through a TiO2 filter at an empty bed contact time of 6 min for 4 months. Approximately 11 000, 14 000, and 9900 bed volumes of water had been treated before the As(III), As(V), and MMA concentration in the effluent increased to 10 ?g L-1. However, very little DMA was removed. The EXAFS results demonstrate the existence of a bidentate binuclear As(V) surface complex on spent adsorbent, indicating the oxidation of adsorbed As(III). A nanocrystalline TiO2-based adsorbent could be used for the simultaneous removal of As(V), As(III), MMA, and DMA in contaminated groundwater.

  19. Application of carbon foam for heavy metal removal from industrial plating wastewater and toxicity evaluation of the adsorbent.

    PubMed

    Lee, Chang-Gu; Song, Mi-Kyung; Ryu, Jae-Chun; Park, Chanhyuk; Choi, Jae-Woo; Lee, Sang-Hyup

    2016-06-01

    Electroplating wastewater contains various types of toxic substances, such as heavy metals, solvents, and cleaning agents. Carbon foam was used as an adsorbent for the removal of heavy metals from real industrial plating wastewater. Its sorption capacity was compared with those of a commercial ion-exchange resin (BC258) and a heavy metal adsorbent (CupriSorb™) in a batch system. The experimental carbon foam has a considerably higher sorption capacity for Cr and Cu than commercial adsorbents for acid/alkali wastewater and cyanide wastewater. Additionally, cytotoxicity test showed that the newly developed adsorbent has low cytotoxic effects on three kinds of human cells. In a pilot plant, the carbon foam had higher sorption capacity for Cr (73.64 g kg(-1)) than for Cu (14.86 g kg(-1)) and Ni (7.74 g kg(-1)) during 350 h of operation time. Oxidation pretreatments using UV/hydrogen peroxide enhance heavy metal removal from plating wastewater containing cyanide compounds. PMID:26999028

  20. Simulations of noble gases adsorbed on graphene

    NASA Astrophysics Data System (ADS)

    Maiga, Sidi; Gatica, Silvina

    2014-03-01

    We present results of Grand Canonical Monte Carlo simulations of adsorption of Kr, Ar and Xe on a suspended graphene sheet. We compute the adsorbate-adsorbate interaction by a Lennard-Jones potential. We adopt a hybrid model for the graphene-adsorbate force; in the hybrid model, the potential interaction with the nearest carbon atoms (within a distance rnn) is computed with an atomistic pair potential Ua; for the atoms at r>rnn, we compute the interaction energy as a continuous integration over a carbon uniform sheet with the density of graphene. For the atomistic potential Ua, we assume the anisotropic LJ potential adapted from the graphite-He interaction proposed by Cole et.al. This interaction includes the anisotropy of the C atoms on graphene, which originates in the anisotropic π-bonds. The adsorption isotherms, energy and structure of the layer are obtained and compared with experimental results. We also compare with the adsorption on graphite and carbon nanotubes. This research was supported by NSF/PRDM (Howard University) and NSF (DMR 1006010).

  1. Orbital tomography for highly symmetric adsorbate systems

    NASA Astrophysics Data System (ADS)

    Stadtmüller, B.; Willenbockel, M.; Reinisch, E. M.; Ules, T.; Bocquet, F. C.; Soubatch, S.; Puschnig, P.; Koller, G.; Ramsey, M. G.; Tautz, F. S.; Kumpf, C.

    2012-10-01

    Orbital tomography is a new and very powerful tool to analyze the angular distribution of a photoemission spectroscopy experiment. It was successfully used for organic adsorbate systems to identify (and consequently deconvolute) the contributions of specific molecular orbitals to the photoemission data. The technique was so far limited to surfaces with low symmetry like fcc(110) oriented surfaces, owing to the small number of rotational domains that occur on such surfaces. In this letter we overcome this limitation and present an orbital tomography study of a 3,4,9,10-perylene-tetra-carboxylic-dianhydride (PTCDA) monolayer film adsorbed on Ag(111). Although this system exhibits twelve differently oriented molecules, the angular resolved photoemission data still allow a meaningful analysis of the different local density of states and reveal different electronic structures for symmetrically inequivalent molecules. We also discuss the precision of the orbital tomography technique in terms of counting statistics and linear regression fitting algorithm. Our results demonstrate that orbital tomography is not limited to low-symmetry surfaces, a finding which makes a broad field of complex adsorbate systems accessible to this powerful technique.

  2. Batch-to-batch pharmacokinetic variability confounds current bioequivalence regulations: A dry powder inhaler randomized clinical trial.

    PubMed

    Burmeister Getz, E; Carroll, K J; Jones, B; Benet, L Z

    2016-09-01

    Current pharmacokinetic (PK) bioequivalence guidelines do not account for batch-to-batch variability in study design or analysis. Here we evaluate the magnitude of batch-to-batch PK variability for Advair Diskus 100/50. Single doses of fluticasone propionate and salmeterol combinations were administered by oral inhalation to healthy subjects in a randomized clinical crossover study comparing three different batches purchased from the market, with one batch replicated across two treatment periods. All pairwise comparisons between different batches failed the PK bioequivalence statistical test, demonstrating substantial PK differences between batches that were large enough to demonstrate bio-inequivalence in some cases. In contrast, between-replicate PK bioequivalence was demonstrated for the replicated batch. Between-batch variance was ∼40-70% of the estimated residual error. This large additional source of variability necessitates re-evaluation of bioequivalence assessment criteria to yield a result that is both generalizable and consistent with the principles of type I and type II error rate control. PMID:27037630

  3. TANK 50 BATCH 0 SALTSTONE FORMULATION CONFIRMATION

    SciTech Connect

    Langton, C.

    2006-06-05

    Savannah River National Laboratory (SRNL) personnel were requested to confirm the Tank 50 Batch 0 grout formulation per Technical Task Request, SSF-TTR-2006-0001 (task 1 of 2) [1]. Earlier Batch 0 formulation testing used a Tank 50 sample collected in September 2005 and is described elsewhere [2]. The current testing was performed using a sample of Tank 50 waste collected in May 2006. This work was performed according to the Technical Task and Quality Assurance Plan (TT/QAP), WSRC-RP-2006-00594 [3]. The salt solution collected from Tank 50 in May 2006 contained approximately 3 weight percent more solids than the sample collected in September 2005. The insoluble solids took longer to settle in the new sample which was interpreted as indicating finer particles in the current sample. The saltstone formulation developed for the September 2005 Tank 50 Batch 0 sample was confirmed for the May 2006 sample with one minor exception. Saltstone prepared with the Tank 50 sample collected in May 2006 required 1.5 times more Daratard 17 set retarding admixture than the saltstone prepared with the September In addition, a sample prepared with lower shear mixing (stirring with a spatula) had a higher plastic viscosity (57 cP) than samples made with higher shear mixing in a blender (23cP). The static gel times of the saltstone slurries made with low shear mixing were also shorter ({approx}32 minutes) than those for comparable samples made in the blender ({approx}47 minutes). The addition of the various waste streams (ETP, HEU-HCAN, and GPE-HCAN) to Tank 50 from September 2005 to May 2006 has increased the amount of set retarder, Daratard 17, required for processing saltstone slurries through the Saltstone facility. If these streams are continued to be added to Tank 50, the quantity of admixtures required to maintain the same processing conditions for the Saltstone facility will probably change and additional testing is recommended to reconfirm the Tank 50 Saltstone formulation.

  4. Adsorption of arsenate from aqueous solution by rice husk-based adsorbent

    NASA Astrophysics Data System (ADS)

    Khan, Taimur; Chaudhuri, Malay

    2013-06-01

    Rice husk-based adsorbent (RHBA) was prepared by burning rice husk in a muffle furnace at 400°C for 4 h and adsorption of arsenate by the RHBA from aqueous solution was examined. Batch adsorption test showed that extent of arsenate adsorption depended on contact time and pH. Equilibrium adsorption was attained in 60 min, with maximum adsorption occurring at pH 7. Equilibrium adsorption data were well described by the Freundlich isotherm model. Freundlich constants Kf and 1/n were 3.62 and 2, respectively. The RHBA is effective in the adsorption of arsenate from water and is a potentially suitable filter medium for removing arsenate from groundwater at wells or in households.

  5. Tc-99 Adsorption on Selected Activated Carbons - Batch Testing Results

    SciTech Connect

    Mattigod, Shas V.; Wellman, Dawn M.; Golovich, Elizabeth C.; Cordova, Elsa A.; Smith, Ronald M.

    2010-12-01

    CH2M HILL Plateau Remediation Company (CHPRC) is currently developing a 200-West Area groundwater pump-and-treat system as the remedial action selected under the Comprehensive Environmental Response, Compensation, and Liability Act Record of Decision for Operable Unit (OU) 200-ZP-1. This report documents the results of treatability tests Pacific Northwest National Laboratory researchers conducted to quantify the ability of selected activated carbon products (or carbons) to adsorb technetium-99 (Tc-99) from 200-West Area groundwater. The Tc-99 adsorption performance of seven activated carbons (J177601 Calgon Fitrasorb 400, J177606 Siemens AC1230AWC, J177609 Carbon Resources CR-1240-AW, J177611 General Carbon GC20X50, J177612 Norit GAC830, J177613 Norit GAC830, and J177617 Nucon LW1230) were evaluated using water from well 299-W19-36. Four of the best performing carbons (J177606 Siemens AC1230AWC, J177609 Carbon Resources CR-1240-AW, J177611 General Carbon GC20X50, and J177613 Norit GAC830) were selected for batch isotherm testing. The batch isotherm tests on four of the selected carbons indicated that under lower nitrate concentration conditions (382 mg/L), Kd values ranged from 6,000 to 20,000 mL/g. In comparison. Under higher nitrate (750 mg/L) conditions, there was a measureable decrease in Tc-99 adsorption with Kd values ranging from 3,000 to 7,000 mL/g. The adsorption data fit both the Langmuir and the Freundlich equations. Supplemental tests were conducted using the two carbons that demonstrated the highest adsorption capacity to resolve the issue of the best fit isotherm. These tests indicated that Langmuir isotherms provided the best fit for Tc-99 adsorption under low nitrate concentration conditions. At the design basis concentration of Tc 0.865 µg/L(14,700 pCi/L), the predicted Kd values from using Langmuir isotherm constants were 5,980 mL/g and 6,870 mL/g for for the two carbons. These Kd values did not meet the target Kd value of 9,000 mL/g. Tests

  6. A batch adsorption study on bentonite clay Pertinence to transport modeling?

    NASA Astrophysics Data System (ADS)

    BOURG, I.; BOURG, A. C.; SPOSITO, G.

    2001-12-01

    Bentonite clay is often used as a component of engineered barriers for the isolation of high-level toxic wastes. This swelling clay is used for its physical (impermeability, self-healing) but also for its chemical properties, mostly a high cation exchange capacity (CEC). The adsorbed cations being temporarily immobilized, this should slow down the release of cations from the waste to the surrounding environment. In order to assess the performance of the engineered barrier, the partitioning of solutes between the liquid and solid phases needs to be quantified for use in transport models. The usual method for characterizing the adsorption is through batch adsorption experiments on dispersed suspensions of the solid, yielding an adsorption isotherm (adsorbed concentration vs. dissolved concentration). This isotherm however should be a function of various environmental variables (e.g., pH, ionic strength, concentrations of various ligands and competing adsorbents), so that extrapolation of lab data to performance assessment in the field is problematic. We present results from a study of the adsorption of cesium, strontium, cadmium and lead on dispersed suspensions of the standard BX-80 bentonite. Through a wide range of experimental parameters (pH, ionic strength, reaction time, reactor open or closed to the atmosphere, study of a range of cations of differing properties), we seek a mechanistic interpretation of the results instead of an empirical determination of adsorption parameters. Depending on the mechanisms that control the adsorption in different experimental ranges, we discuss the degree to which the partitioning coefficient (Kd) obtained in the lab can be extrapolated to a transport model through compacted bentonite in a natural environment.

  7. Arsenate removal by layered double hydroxides embedded into spherical polymer beads: Batch and column studies.

    PubMed

    Nhat Ha, Ho Nguyen; Kim Phuong, Nguyen Thi; Boi An, Tran; Mai Tho, Nguyen Thi; Ngoc Thang, Tran; Quang Minh, Bui; Van Du, Cao

    2016-01-01

    In this study, the performance of poly(layered double hydroxides) [poly(LDHs)] beads as an adsorbent for arsenate removal from aqueous solution was investigated. The poly(LDHs) beads were prepared by immobilizing LDHs into spherical alginate/polyvinyl alcohol (PVA)-glutaraldehyde beads (spherical polymer beads). Batch adsorption studies were conducted to assess the effect of contact time, solution pH, initial arsenate concentrations and co-existing anions on arsenate removal performance. The potential reuse of these poly(LDHs) beads was also investigated. Approximately 79.1 to 91.2% of arsenic was removed from an arsenate solution (50 mg As L(-1)) by poly(LDHs). The adsorption data were well described by the pseudo-second-order kinetics model and the Langmuir isotherm model, and the adsorption capacities of these poly(LDHs) beads at pH 8 were from 1.64 to 1.73 mg As g(-1), as calculated from the Langmuir adsorption isotherm. The adsorption ability of the poly(LDHs) beads decreased by approximately 5-6% after 5 adsorption-desorption cycles. Phosphates markedly decreased arsenate removal. The effect of co-existing anions on the adsorption capacity declined in the following order: HPO4 (2-) > HCO3 (-) > SO4 (2-) > Cl(-). A fixed-bed column study was conducted with real-life arsenic-containing water. The breakthrough time was found to be from 7 to 10 h. Under optimized conditions, the poly(LDHs) removed more than 82% of total arsenic. The results obtained in this study will be useful for further extending the adsorbents to the field scale or for designing pilot plants in future studies. From the viewpoint of environmental friendliness, the poly(LDHs) beads are a potential cost-effective adsorbent for arsenate removal in water treatment. PMID:26818806

  8. Reactive Scheduling in Multipurpose Batch Plants

    NASA Astrophysics Data System (ADS)

    Narayani, A.; Shaik, Munawar A.

    2010-10-01

    Scheduling is an important operation in process industries for improving resource utilization resulting in direct economic benefits. It has a two-fold objective of fulfilling customer orders within the specified time as well as maximizing the plant profit. Unexpected disturbances such as machine breakdown, arrival of rush orders and cancellation of orders affect the schedule of the plant. Reactive scheduling is generation of a new schedule which has minimum deviation from the original schedule in spite of the occurrence of unexpected events in the plant operation. Recently, Shaik & Floudas (2009) proposed a novel unified model for short-term scheduling of multipurpose batch plants using unit-specific event-based continuous time representation. In this paper, we extend the model of Shaik & Floudas (2009) to handle reactive scheduling.

  9. Batch sequential designs for computer experiments

    SciTech Connect

    Moore, Leslie M; Williams, Brian J; Loeppky, Jason L

    2009-01-01

    Computer models simulating a physical process are used in many areas of science. Due to the complex nature of these codes it is often necessary to approximate the code, which is typically done using a Gaussian process. In many situations the number of code runs available to build the Guassian process approximation is limited. When the initial design is small or the underlying response surface is complicated this can lead to poor approximations of the code output. In order to improve the fit of the model, sequential design strategies must be employed. In this paper we introduce two simple distance based metrics that can be used to augment an initial design in a batch sequential manner. In addition we propose a sequential updating strategy to an orthogonal array based Latin hypercube sample. We show via various real and simulated examples that the distance metrics and the extension of the orthogonal array based Latin hypercubes work well in practice.

  10. Reducing variance in batch partitioning measurements

    SciTech Connect

    Mariner, Paul E.

    2010-08-11

    The partitioning experiment is commonly performed with little or no attention to reducing measurement variance. Batch test procedures such as those used to measure K{sub d} values (e.g., ASTM D 4646 and EPA402 -R-99-004A) do not explain how to evaluate measurement uncertainty nor how to minimize measurement variance. In fact, ASTM D 4646 prescribes a sorbent:water ratio that prevents variance minimization. Consequently, the variance of a set of partitioning measurements can be extreme and even absurd. Such data sets, which are commonplace, hamper probabilistic modeling efforts. An error-savvy design requires adjustment of the solution:sorbent ratio so that approximately half of the sorbate partitions to the sorbent. Results of Monte Carlo simulations indicate that this simple step can markedly improve the precision and statistical characterization of partitioning uncertainty.

  11. Acoustic microstreaming applied to batch micromixing

    NASA Astrophysics Data System (ADS)

    Manasseh, Richard; Petkovic-Duran, Karolina; Tho, Paul; Zhu, Yonggang; Ooi, Andrew

    2006-01-01

    Experiments are presented in which acoustic microstreaming is investigated and applied to a batch micromixing case appropriate to a point-of-care pathology screening test. The flows presented can be created without complex engineering of contacts or surfaces in the microdevice, which could thus be made disposable. Fundamental flow patterns are measured with a micro-Particle-Image Velocimetry (micro-PIV) system, enabling a quantification of the fluiddynamical processes causing the flows. The design of micromixers based on this principle requires a quantification of the mixing. A simple technique based on digital image processing is presented that enables an assessment of the improvement in mixing due to acoustic microstreaming. The digital image processing technique developed was shown to be non-intrusive, convenient and able to generate useful quantitative data. Preliminary indications are that microstreaming can at least halve the time required to mix quantities of liquid typical of a point-of-care test, and significantly greater improvements seem feasible.

  12. Batch-to-batch uniformity of bacterial community succession and flavor formation in the fermentation of Zhenjiang aromatic vinegar.

    PubMed

    Wang, Zong-Min; Lu, Zhen-Ming; Yu, Yong-Jian; Li, Guo-Quan; Shi, Jin-Song; Xu, Zheng-Hong

    2015-09-01

    Solid-state fermentation of traditional Chinese vinegar is a mixed-culture refreshment process that proceeds for many centuries without spoilage. Here, we investigated bacterial community succession and flavor formation in three batches of Zhenjiang aromatic vinegar using pyrosequencing and metabolomics approaches. Temporal patterns of bacterial succession in the Pei (solid-state vinegar culture) showed no significant difference (P > 0.05) among three batches of fermentation. In all the batches investigated, the average number of community operational taxonomic units (OTUs) decreased dramatically from 119 ± 11 on day 1 to 48 ± 16 on day 3, and then maintained in the range of 61 ± 9 from day 5 to the end of fermentation. We confirmed that, within a batch of fermentation process, the patterns of bacterial diversity between the starter (took from the last batch of vinegar culture on day 7) and the Pei on day 7 were similar (90%). The relative abundance dynamics of two dominant members, Lactobacillus and Acetobacter, showed high correlation (coefficient as 0.90 and 0.98 respectively) among different batches. Furthermore, statistical analysis revealed dynamics of 16 main flavor metabolites were stable among different batches. The findings validate the batch-to-batch uniformity of bacterial community succession and flavor formation accounts for the quality of Zhenjiang aromatic vinegar. Based on our understanding, this is the first study helps to explain the rationality of age-old artistry from a scientific perspective. PMID:25998816

  13. Conformational properties of an adsorbed charged polymer.

    PubMed

    Cheng, Chi-Ho; Lai, Pik-Yin

    2005-06-01

    The behavior of a strongly charged polymer adsorbed on an oppositely charged surface of a low-dielectric constant is formulated by the functional integral method. By separating the translational, conformational, and fluctuational degrees of freedom, the scaling behaviors for both the height of the polymer and the thickness of the diffusion layer are determined. Unlike the results predicted by scaling theory, we identified the continuous crossover from the weak compression to the compression regime. All the analytical results are found to be consistent with Monte Carlo simulations. Finally, an alternative (operational) definition of a charged polymer adsorption is proposed. PMID:16089715

  14. Recovery of Technetium Adsorbed on Charcoal

    SciTech Connect

    Engelmann, Mark D.; Metz, Lori A.; Ballou, Nathan E.

    2006-05-01

    Two methods capable of near complete recovery of technetium adsorbed on charcoal are presented. The first involves liquid extraction of the technetium from the charcoal by hot 4M nitric acid. An average recovery of 98% (n=3) is obtained after three rounds of extraction. The second method involves dry ashing with air in a quartz combustion tube at 400-450 C. This method yields an average recovery of 96% (n=5). Other thermal methods were attempted, but resulted in reduced recovery and incomplete material balance

  15. Lead removal with adsorbing colloid flotation

    SciTech Connect

    Thackston, E.L.; Wilson, D.J.; Hanson, J.S.; Miller, D.L. Jr.

    1980-02-01

    A process that removes lead from industrial waste by adsorbing colloid foam flotation has been designed and demonstrated. A system of ferric chloride and sodium lauryl sulfate, both relatively inexpensive chemicals, gave good performance with optimum dosages of sodium lauryl sulfate at 40 mg/l and trivalent iron at 150 mg/l. With optimum chemical and hydraulic conditions, the pilot plant was able to produce effluents with lead concentrations of less than 0.5 mg/l. The process may be especially attractive where space for heavy metals removal equipment is extremely limited.

  16. Evaluation of vermicompost as a raw natural adsorbent for adsorption of pesticide methylparathion.

    PubMed

    Mendes, Camila Bitencourt; Lima, Giovana de Fátima; Alves, Vanessa Nunes; Coelho, Nívia Maria Melo; Dragunski, Douglas Cardoso; Tarley, César Ricardo Teixeira

    2012-01-01

    The assessment of vermicompost (VC) as a low-cost and alternative adsorbent for the removal of the pesticide methylparathion (MP) from an aqueous medium has been investigated by batch and column experiments. Parameters related to MP adsorption, i.e. equilibrium time (61.5 min) and adsorption pH (6.8) were optimized by using Doehlert design. The initial and final MP concentrations after adsorption assays were determined by square-wave adsorptive cathodic stripping voltammetry using an electrode composed of a multiwalled carbon nanotube dispersed in mineral oil. Batch adsorption experimental data were fitted to the Langmuir and Freundlich isotherm adsorptions, and a very good fit to the Langmuir linear model, giving a maximum adsorption capacity (MAC) of 0.17 mg g(-1). This result was very similar to that obtained with the column experiments. In order to evaluate the MP desorption from column packed VC, 100.0 ml of nitric acid solution (pH 3.0) has been percolated through material. No leaching of MP was observed, thus confirming the strong interaction between MP and VC. The satisfactory MAC obtained and low cost makes the VC a reliable natural material for the removal of MP from aqueous effluents. PMID:22519100

  17. Removal of copper ions from aqueous solution by adlai shell (Coix lacryma-jobi L.) adsorbents.

    PubMed

    de Luna, Mark Daniel G; Flores, Edgar D; Cenia, Marie Chela B; Lu, Ming-Chun

    2015-09-01

    Adlai shell (Coix lacryma-jobi L.) adsorbents (ASA) were used to remove copper ions from aqueous solutions under batch conditions. The effect of physical and chemical modification of ASA on Cu(II) removal was evaluated. Results showed that the high coefficients of determination for the pseudo-second order (R(2) > 0.9999) and for the intraparticle diffusion (R(2) > 0.9843) equations indicate that the rate-determining step is a combination of pore diffusion and chemisorption at low Cu(II) concentration and boundary layer, pore diffusion and chemisorption at high Cu(II) concentration. At 298K and 100 mg L(-1) Cu(II), the computed qe and k2 values were 17.2 mg g(-1) and 0.012 g mg(-1) min(-1), respectively. The Freundlich model (R(2) > 0.9636) adequately describes the experimental data indicating heterogeneous adsorption. Overall, the results of the study demonstrate the potential of adlai shell adsorbents for the removal of heavy metals from aqueous solutions. PMID:26081160

  18. Cadmium telluride nanoparticles loaded on activated carbon as adsorbent for removal of sunset yellow.

    PubMed

    Ghaedi, M; Hekmati Jah, A; Khodadoust, S; Sahraei, R; Daneshfar, A; Mihandoost, A; Purkait, M K

    2012-05-01

    Adsorption is a promising technique for decolorization of effluents of textile dyeing industries but its application is limited due to requirement of high amounts of adsorbent required. The objective of this study was to assess the potential of cadmium telluride nanoparticles loaded onto activated carbon (CdTN-AC) for the removal of sunset yellow (SY) dye from aqueous solution. Adsorption studies were conducted in a batch mode varying solution pH, contact time, initial dye concentration, CdTN-AC dose, and temperature. In order to investigate the efficiency of SY adsorption on CdTN-AC, pseudo-first-order, pseudo-second-order, Elovich, and intra-particle diffusion kinetic models were studied. It was observed that the pseudo-second-order kinetic model fits better than other kinetic models with good correlation coefficient. Equilibrium data were fitted to the Langmuir model. Thermodynamic parameters such as enthalpy, entropy, activation energy, and sticking probability were also calculated. It was found that the sorption of SY onto CdTN-AC was spontaneous and endothermic in nature. The proposed adsorbent is applicable for SY removal from waste of real effluents including pea-shooter, orange drink and jelly banana with efficiency more than 97%. PMID:22306446

  19. Cadmium telluride nanoparticles loaded on activated carbon as adsorbent for removal of sunset yellow

    NASA Astrophysics Data System (ADS)

    Ghaedi, M.; Hekmati Jah, A.; Khodadoust, S.; Sahraei, R.; Daneshfar, A.; Mihandoost, A.; Purkait, M. K.

    2012-05-01

    Adsorption is a promising technique for decolorization of effluents of textile dyeing industries but its application is limited due to requirement of high amounts of adsorbent required. The objective of this study was to assess the potential of cadmium telluride nanoparticles loaded onto activated carbon (CdTN-AC) for the removal of sunset yellow (SY) dye from aqueous solution. Adsorption studies were conducted in a batch mode varying solution pH, contact time, initial dye concentration, CdTN-AC dose, and temperature. In order to investigate the efficiency of SY adsorption on CdTN-AC, pseudo-first-order, pseudo-second-order, Elovich, and intra-particle diffusion kinetic models were studied. It was observed that the pseudo-second-order kinetic model fits better than other kinetic models with good correlation coefficient. Equilibrium data were fitted to the Langmuir model. Thermodynamic parameters such as enthalpy, entropy, activation energy, and sticking probability were also calculated. It was found that the sorption of SY onto CdTN-AC was spontaneous and endothermic in nature. The proposed adsorbent is applicable for SY removal from waste of real effluents including pea-shooter, orange drink and jelly banana with efficiency more than 97%.

  20. Alkaline deoxygenated graphene oxide as adsorbent for cadmium ions removal from aqueous solutions.

    PubMed

    Liu, Jun; Du, Hongyan; Yuan, Shaowei; He, Wanxia; Yan, Pengju; Liu, Zhanhong

    2015-01-01

    Alkaline deoxygenated graphene oxide (aGO) was prepared through alkaline hydrothermal treatment and used as adsorbent to remove Cd(II) ions from aqueous solutions for the first time. The characterization results of transmission electron microscopy, X-ray diffraction, Raman spectroscopy, and Fourier transform infrared (FT-IR) spectra indicate that aGO was successfully synthesized. The batch adsorption experiments showed that the adsorption kinetics could be described by the pseudo-second-order kinetic model, and the isotherms equilibrium data were well fitted with the Langmuir model. The maximum adsorption capacity of Cd(II) on aGO was 156 mg/g at pH 5 and T=293 K. The adsorption thermodynamic parameters indicated that the adsorption process was a spontaneous and endothermic reaction. The mainly adsorption mechanism speculated from FT-IR results may be attributed to the electrostatic attraction between Cd2+ and negatively charged groups (-CO-) of aGO and cation-π interaction between Cd2+ and the graphene planes. The findings of this study demonstrate the potential utility of the nanomaterial aGO as an effective adsorbent for Cd(II) removal from aqueous solutions. PMID:26038925

  1. Investigation on the adsorption of phosphorus by Fe-loaded ceramic adsorbent.

    PubMed

    Wang, Di; Chen, Nan; Yu, Yang; Hu, Weiwu; Feng, Chuanping

    2016-02-15

    This aim of this study was to remove phosphorus from aqueous solution using a Fe-loaded ceramic (Fe-LC) adsorbent prepared by mixing dolomite, montmorillonite, FeSO4·7H2O and starch. Simplex-centroid mixture design method was used to determine the optimum mixture proportions by evaluating both phosphorus adsorption efficiency and adsorbent hardness. The study found that the optimum adsorption capacity and the strength can be achieved with the composition of 3.87g dolomite, 3.00g starch, 2.13g montmorillonite and 1.00g FeSO4·7H2O (10g in total). The optimized Fe-LC was evaluated in the batch and the fixed bed experiments. The point of zero charge, pHpzc was found to be 6.0. The adsorption kinetic and isotherm data well agreed with the pseudo-second-order kinetic and the Langmuir isotherm models, respectively. The breakthrough time increased with increasing in the bed depth, whereas inverse relationship was observed with the initial phosphorus concentration in the fixed bed studies. The co-existing anions (SO4(2-), NO3(-) and Cl(-)) had negligible influence on phosphorus removal. The BDST and Thomas model explained the breakthrough behavior for phosphorus removal with a high degree of correlation. PMID:26624533

  2. Process development for removal of substituted phenol by carbonaceous adsorbent obtained from fertilizer waste

    SciTech Connect

    Srivastava, S.K.; Mohan, D.; Tyagi, R.; Pal, N.

    1997-09-01

    Waste slurry, generated in local fertilizer plants, is converted into a cheap carbonaceous material. The product so obtained has been characterized and utilized for the removal of 2,4-dinitrophenol (DNP). The removal of DNP is 100% weight-to-weight (w/w) at low concentrations, while it is 80% w/w at higher concentrations. Several factors affecting the removal of DNP from water (e.g., particle size distribution, solution pH, contact time, loading of DNP on the adsorbent, etc.) have been studied at optimum pH (4.0). Both batch and column studies were performed. The adsorption capacities, adsorption rates, and break-through curves are used to optimize the contactors and identify design correlations. Some feasibility experiments have been performed, with an aim to recover DNP and chemical regeneration of the spent column. It is observed that 60 mL of 5% w/w NaOH is sufficient for almost complete desorption of DNP (loaded 57.5 mg, desorbed 55.2 mg). After regeneration with 1M HNO{sub 3}, the sorption capacity of the column is almost the same as that of virgin adsorbent material.

  3. Investigation of organic, inorganic and synthetic adsorbents for the pretreatment of landfill leachate.

    PubMed

    Shahriari, H; Fernandes, L; Tezel, F H

    2008-05-01

    An investigation into the use of organic, inorganic and synthetic adsorbents for the pretreatment of landfill leachate, generated by the City of Ottawa Trail Road Landfill, was carried out. The purpose of this project was to reduce the concentration of contaminants in order to meet the local Sewer Use By-Laws, prior to transporting the leachate from the generating site to the local municipal sewage treatment plant, and thereby reducing the disposal fees. Peat moss, compost, clinoptilolite, basalt and two types of activated carbon (DSR-A and F400) were investigated to determine the adsorption capacity for contaminants from leachate. Kinetic studies were also performed. The results based on batch adsorption isotherms show that peat moss has the highest adsorption capacity for boron (B) and barium (Ba), compared with the other adsorbents. Also peat moss has good removals of Total Kjeldahl Nitrogen (TKN), Total Organic Carbon (TOC), and benzene, toluene, ethylbenzene and xylene (BTEX), but these are lower than the removals obtained with activated carbon. Because of its relatively low cost and higher adsorption of B and Ba, peat moss was selected as the filter media for the column studies. The treated leachate was tested for B, Ba, TKN, carbonaceous biological oxygen demand (CBOD5) and hydrogen sulfide (H2S). The breakthrough curves for B and Ba showed the effectiveness of peat moss in removing these contaminants. PMID:18661738

  4. Searching CA Condensates, On-Line and Batch.

    ERIC Educational Resources Information Center

    Kaminecki, Ronald M.; And Others

    Batch mode processing is compared, using cost-effectiveness, with on-line processing for computer-aided searching of chemical abstracts. Consideration for time, need, coverage, and adaptability are found to be the criteria by which a searcher selects a method, and sometimes both methods are used. There is a tradeoff between batch mode's slower…

  5. INTERIOR VIEW SHOWING BATCH SCALES. SERIES OF FIVE SCALES WITH ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    INTERIOR VIEW SHOWING BATCH SCALES. SERIES OF FIVE SCALES WITH SIX DIFFERENT MATERIALS. MIX SIFTED DOWN FROM SILOS ABOVE. INGREDIENTS: SAND, SODA ASH, DOLOMITE LIMESTONE, NEPHELINE SYENITE, SALT CAKE. - Chambers-McKee Window Glass Company, Batch Plant, Clay Avenue Extension, Jeannette, Westmoreland County, PA

  6. 40 CFR Table 1 to Subpart H of... - Batch Processes

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 10 2012-07-01 2012-07-01 false Batch Processes 1 Table 1 to Subpart H... Standards for Organic Hazardous Air Pollutants for Equipment Leaks Pt. 63, Subpt. H, Table 1 Table 1 to Subpart H of Part 63—Batch Processes Monitoring Frequency for Equipment Other than Connectors...

  7. 40 CFR Table 1 to Subpart H of... - Batch Processes

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 10 2013-07-01 2013-07-01 false Batch Processes 1 Table 1 to Subpart H... Standards for Organic Hazardous Air Pollutants for Equipment Leaks Pt. 63, Subpt. H, Table 1 Table 1 to Subpart H of Part 63—Batch Processes Monitoring Frequency for Equipment Other than Connectors...

  8. 40 CFR Table 1 to Subpart H of... - Batch Processes

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 10 2014-07-01 2014-07-01 false Batch Processes 1 Table 1 to Subpart H... Subpart H of Part 63—Batch Processes Monitoring Frequency for Equipment Other than Connectors Operating time (% of year) Equivalent continuous process monitoring frequency time in use Monthly...

  9. 40 CFR Table 1 to Subpart H of... - Batch Processes

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 9 2010-07-01 2010-07-01 false Batch Processes 1 Table 1 to Subpart H... Subpart H of Part 63—Batch Processes Monitoring Frequency for Equipment Other than Connectors Operating time (% of year) Equivalent continuous process monitoring frequency time in use Monthly...

  10. 40 CFR Table 1 to Subpart H of... - Batch Processes

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 9 2011-07-01 2011-07-01 false Batch Processes 1 Table 1 to Subpart H... Standards for Organic Hazardous Air Pollutants for Equipment Leaks Pt. 63, Subpt. H, Table 1 Table 1 to Subpart H of Part 63—Batch Processes Monitoring Frequency for Equipment Other than Connectors...

  11. IMPLEMENTATION OF SEQUENCING BATCH REACTORS FOR MUNICIPAL TREATMENT

    EPA Science Inventory

    Sequencing batch reactor technology is being implemented at various municipal sites in both the United States and abroad. Total life cycle cost savings, ease of operation, and reliability favor this technology at facilities sized up to 19,000 cu m per day (5 mgd). Batch treatment...

  12. System Requirements for On-Line and Batch Retrieval.

    ERIC Educational Resources Information Center

    American Society for Information Science, Washington, DC. Special Interest Group on Computerized Retrieval Services.

    Three papers on system requirements for on-line and batch retrieval presented at the American Society for Information Science (ASIS) annual meeting are included here. At G.D. Searle, data for records related to pharmacology screening are used in a batch system, and an on-line system is used to search information on mutagenic, carcinogenic, and…

  13. 27 CFR 19.598 - Dump/batch records.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2013-04-01 2013-04-01 false Dump/batch records. 19.598 Section 19.598 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY ALCOHOL DISTILLED SPIRITS PLANTS Records and Reports Processing Records § 19.598 Dump/batch records. A proprietor...

  14. Optimizing heterosurface adsorbent synthesis for liquid chromatography

    NASA Astrophysics Data System (ADS)

    Bogoslovskii, S. Yu.; Serdan, A. A.

    2016-03-01

    The structural and geometric parameters of a silica matrix (SM) for the synthesis of heterosurface adsorbents (HAs) are optimized. Modification is performed by shielding the external surfaces of alkyl-modified silica (AS) using human serum albumin and its subsequent crosslinking. The structural and geometric characteristics of the SM, AS, and HA are measured via low-temperature nitrogen adsorption. It is found that the structural characteristics of AS pores with diameters D < 6 nm do not change during HA synthesis, while the volume of pores with diameters of 6 nm < D < 9 nm shrinks slightly due to the adsorption of albumin in the pore orifices. It is established that the volume of pores with diameters D > 9 nm reduces significantly due to adsorption of albumin. It is concluded that silica gel with a maximum pore size distribution close to 5 nm and a minimal proportion of pores with D > 9 nm is optimal for HA synthesis; this allows us to achieve the greatest similarity between the chromatographic retention parameters for HA and AS. The suitability of the synthesized adsorbents for analyzing drugs in biological fluids through direct sample injection is confirmed by chromatography. It was found that the percentage of the protein fraction detected at the outlet of the chromatographic column is 98%.

  15. Nitric oxide releasing material adsorbs more fibrinogen.

    PubMed

    Lantvit, Sarah M; Barrett, Brittany J; Reynolds, Melissa M

    2013-11-01

    One mechanism of the failure of blood-contacting devices is clotting. Nitric oxide (NO) releasing materials are seen as a viable solution to the mediation of surface clotting by preventing platelet activation; however, NO's involvement in preventing clot formation extends beyond controlling platelet function. In this study, we evaluate NO's effect on factor XII (fibrinogen) adsorption and activation, which causes the initiation of the intrinsic arm of the coagulation cascade. This is done by utilizing a model plasticized poly(vinyl) chloride (PVC), N-diazeniumdiolate system and looking at the adsorption of fibrinogen, an important clotting protein, to these surfaces. The materials have been prepared in such a way to eliminate changes in surface properties between the control (plasticized PVC) and composite (NO-releasing) materials. This allows us to isolate NO release and determine the effect on the adsorption of fibrinogen, to the material surface. Surprisingly, it was found that an NO releasing material with a surface flux of 17.4 ± 0.5 × 10(-10) mol NO cm(-2) min(-1) showed a significant increase in the amount of fibrinogen adsorbed to the material surface compared to one with a flux of 13.0 ± 1.6 × 10(-10) mol NO cm(-2) min(-1) and the control (2334 ± 496, 226 ± 99, and 103 ±31% fibrinogen adsorbed of control, respectively). This study suggests that NO's role in controlling clotting is extended beyond platelet activation. PMID:23554300

  16. Adsorbents as antiendotoxin agents in experimental colitis.

    PubMed Central

    Gardiner, K R; Anderson, N H; McCaigue, M D; Erwin, P J; Halliday, M I; Rowlands, B J

    1993-01-01

    The intestinal mucosa protects the body from a large reservoir of intraluminal pathogenic bacteria and endotoxins. This mucosal barrier is disrupted by the inflammation and ulceration of inflammatory bowel disease and may permit the absorption of toxic bacterial products. Systemic endotoxaemia has been demonstrated in ulcerative colitis and Crohn's disease and correlates with the extent and activity of disease. In this study the efficacy of absorbents as antiendotoxin agents in a hapten induced rat model of colitis is investigated. Induction of colitis was associated with systemic endotoxaemia. Enteral administration of terra fullonica and kaolin, but not of charcoal, significantly reduced systemic endotoxaemia (terra fullonica 4.2 (1.40) pg/ml; kaolin 5.29 (1.86) pg/ml; charcoal 32.7 (16.6) pg/ml; water 39.8 (12.6) pg/ml). Data expressed as mean (SE). With increasing severity of colitis, there was a decreasing ability of adsorbent therapy (terra fullonica) to control systemic endotoxaemia. Enteral administration of adsorbents controls gut derived systemic endotoxaemia in experimental colitis in animals and may be a useful antiendotoxin treatment in patients with inflammatory bowel disease. PMID:8432452

  17. Block copolymer adsorbed layers on solids

    NASA Astrophysics Data System (ADS)

    Sen, Mani; Jiang, Naisheng; Gowd, Bhoje; Endoh, Maya; Koga, Tadanori

    Block copolymer thin films offer a simple and effective route to fabricate highly ordered periodic microdomain structures. The fundamental, yet unsolved question is whether these highly oriented microdomain structures persist even near an impenetrable solid wall. We here report the adsorbed structures of polystyrene-block-poly (4-vinylpyridine) (PS-block-P4VP, Mw = 41,000, PS (weight fraction =0.81) formed on planar silicon substrates. Perpendicularly aligned cylindrical microdomains were created by solvent vapor annealing (Gowd et al., Soft Matter, 2014, 10, 7753), and the adsorbed layer was derived by solvent leaching with chloroform, a good solvent for the polymers and thereafter characterized by using atomic force microscopy, scanning electron microscopy, grazing incidence small angle x-ray scattering, and x-ray reflectivity. The results showed that both PS and P4VP chains lie flat on the substrate, forming a microphase-separated structure (MSS) without long-range order. Moreover, a spin-coated PS-block-P4VP thin film annealed under vacuum at 190 °C showed similar MSS on the substrate, indicating the generality of the interfacial polymer structure. Details will be discussed in the presentation. NSF Grant No. CMMI-1332499.

  18. Mimetite Formation from Goethite-Adsorbed Ions.

    PubMed

    Kleszczewska-Zębala, Anna; Manecki, Maciej; Bajda, Tomasz; Rakovan, John; Borkiewicz, Olaf J

    2016-06-01

    Bioavailability of arsenic in contaminated soils and wastes can be reduced to insignificant levels by precipitation of mimetite Pb5(AsO4)3Cl. The objective of this study is to elucidate mechanisms of the reaction between solution containing lead ions and arsenates adsorbed on synthetic goethite (AsO4-goethite), or arsenate ions in the solution and goethite saturated with adsorbed Pb (Pb-goethite). These reactions, in the presence of Cl, result in rapid crystallization of mimetite. Formation of mimetite is faster than desorption of AsO4 but slower than desorption of Pb from the goethite surface. Slow desorption of arsenates from AsO4-goethite results in heterogeneous precipitation and formation of mimetite incrustation on goethite crystals. Desorption of lead from Pb-goethite is at least as fast as diffusion and advection of AsO4 and Cl in suspension allowing for homogeneous crystallization of mimetite in intergranular solution. Therefore, the mechanism of nucleation is primarily driven by the kinetics of constituent supply to the saturation front, rather than by the thermodynamics of nucleation. The products of the reactions are well documented using microscopy methods such as scanning electron microscopy, electron backscattered diffraction, X-ray diffraction, and Fourier transform infrared spectroscopy. PMID:27329315

  19. The persistence length of adsorbed dendronized polymers.

    PubMed

    Grebikova, Lucie; Kozhuharov, Svilen; Maroni, Plinio; Mikhaylov, Andrey; Dietler, Giovanni; Schlüter, A Dieter; Ullner, Magnus; Borkovec, Michal

    2016-07-21

    The persistence length of cationic dendronized polymers adsorbed onto oppositely charged substrates was studied by atomic force microscopy (AFM) and quantitative image analysis. One can find that a decrease in the ionic strength leads to an increase of the persistence length, but the nature of the substrate and of the generation of the side dendrons influence the persistence length substantially. The strongest effects as the ionic strength is being changed are observed for the fourth generation polymer adsorbed on mica, which is a hydrophilic and highly charged substrate. However, the observed dependence on the ionic strength is much weaker than the one predicted by the Odijk, Skolnik, and Fixman (OSF) theory for semi-flexible chains. Low-generation polymers show a variation with the ionic strength that resembles the one observed for simple and flexible polyelectrolytes in solution. For high-generation polymers, this dependence is weaker. Similar dependencies are found for silica and gold substrates. The observed behavior is probably caused by different extents of screening of the charged groups, which is modified by the polymer generation, and to a lesser extent, the nature of the substrate. For highly ordered pyrolytic graphite (HOPG), which is a hydrophobic and weakly charged substrate, the electrostatic contribution to the persistence length is much smaller. In the latter case, we suspect that specific interactions between the polymer and the substrate also play an important role. PMID:27353115

  20. Photodecomposition of chloromethanes adsorbed on silica surfaces

    NASA Technical Reports Server (NTRS)

    Ausloos, P.; Rebbert, R. E.; Glasgow, L.

    1977-01-01

    Irradiation of CCl4, CFCl3, and CF2Cl2 in the presence of C2H6 in vessels containing silica sand or fused quartz tubing results in the formation of chlorine-containing products. The formation of these compounds occurs at wavelengths extending up to approximately 400 nm, that is, at wavelengths well beyond the absorption threshold of the chloromethanes in the gas phase. It is suggested that CCl4 adsorbed on silica surfaces photodissociates to yield CCl3 and CCl2 species. The poor material balance obtained in these experiments indicates that several of the chlorine-containing fragments are strongly adsorbed on the surface. At a CCl4 pressure of 13 Pa (0.1 torr), photolysis with 366 nm light in the presence of sand results in the decomposition of one molecule for every 10,000 photons striking the surface. Under otherwise identical conditions, the photon-induced breadkdown of CFCl3 and CF2Cl2 is respectively only 10% or 3% as efficient.

  1. Investigation of drug-porous adsorbent interactions in drug mixtures with selected porous adsorbents.

    PubMed

    Madieh, Shadi; Simone, Michael; Wilson, Wendy; Mehra, Dev; Augsburger, Larry

    2007-04-01

    The adsorption of drugs onto porous substrates may prove to be a convenient method by which to enhance the dissolution rate of certain poorly water-soluble drugs in body fluids. The purpose of this research is to provide a better understanding of the type of interactions occurring between drugs and certain pharmaceutically acceptable porous adsorbents that leads to enhanced drug dissolution rates. The interactions between ibuprofen (acidic drug), acetaminophen (acidic drug), dipyridamole (basic drug), and the porous adsorbents used (calcium silicate and silica gel) were investigated using differential scanning calorimetry (DSC), powder X-ray diffraction (PXRD), and Fourier Transform infrared spectroscopy (FTIR). DSC and PXRD results indicated a significant loss of crystallinity of both ibuprofen and acetaminophen but not dipyridamole. In the case of ibuprofen, FTIR results indicated the ionization of the carboxylic group based on the shift in the FTIR carboxylic band. Dissolution of ibuprofen from its mixtures with porous adsorbents was found to be significantly higher compared to the neat drug, whereas dipyridamole dissolution from its mixtures with porous adsorbents was not significantly different from that of the neat drug. PMID:17221849

  2. Equilibrium molecular theory of two-dimensional adsorbate drops on surfaces of heterogeneous adsorbents

    NASA Astrophysics Data System (ADS)

    Tovbin, Yu. K.

    2016-08-01

    A molecular statistical theory for calculating the linear tension of small multicomponent droplets in two-dimensional adsorption systems is developed. The theory describes discrete distributions of molecules in space (on a scale comparable to molecular size) and continuous distributions of molecules (at short distances inside cells) in their translational and vibrational motions. Pair intermolecular interaction potentials (the Mie type potential) in several coordination spheres are considered. For simplicity, it is assumed that distinctions in the sizes of mixture components are slight and comparable to the sizes of adsorbent adsorption centers. Expressions for the pressure tensor components inside small droplets on the heterogeneous surface of an adsorbent are obtained, allowing calculations of the thermodynamic characteristics of a vapor-fluid interface, including linear tension. Problems in refining the molecular theory are discussed: describing the properties of small droplets using a coordination model of their structure, considering the effect an adsorbate has on the state of a near-surface adsorbent region, and the surface heterogeneity factor in the conditions for the formation of droplets.

  3. Dynamic behaviour of Cd2+ adsorption in equilibrium batch studies by CaCO3(-)-rich Corbicula fluminea shell.

    PubMed

    Ismail, Farhah Amalya; Aris, Ahmad Zaharin; Latif, Puziah Abdul

    2014-01-01

    This work presents the structural and adsorption properties of the CaCO3(-)-rich Corbicula fluminea shell as a natural and economic adsorbent to remove Cd ions from aqueous solutions under batch studies. Experiments were conducted with different contact times, various initial concentrations, initial solution pH and serial biosorbent dosage to examine the dynamic characterization of the adsorption and its influence on Cd uptake capacity. The characterization of the C. fluminea shell using SEM/EDX revealed that the adsorbent surface is mostly impregnated by small particles of potentially calcium salts. The dominant Cd adsorption mechanism is strongly pH and concentration dependent. A maximum Cd removal efficiency of 96.20% was obtained at pH 7 while the optimum adsorbent dosage was observed as 5 g/L. The Langmuir isotherm was discovered to be more suitable to represent the experimental equilibrium isotherm results with higher correlation coefficients (R(2) > 0.98) than Freundlich (R(2) < 0.97).The correlation coefficient values (p < 0.01) indicated the superiority of the Langmuir isotherm over the Freundlich isotherm. PMID:23771443

  4. Dynamic Simulation of Batch Photocatalytic Reactor (BPR) for Wastewater Treatment

    NASA Astrophysics Data System (ADS)

    Dutta, Suman

    2012-08-01

    Reactive dyes discharged from dyehouse causes a serious environmental problem. UV/TiO2 photocatalysis has been employed effectively for these organic dyes removal from dye-house effluent. This process produces less amount of non-toxic final product. In this paper a photocatalytic reactor has been designed for Reactive red 198 (RR198) removal from aqueous solution. The reactor is operating in batch mode. After each batch, TiO2 catalyst has been separated and recycled in the next batch. Mathematical model equation of this batch photocatalytic reactor (BPR) has been developed considering Langmuir-Hinshelwood kinetics. Simulation of BPR has been carried out using fourth order Runge-Kutta (RK) method and fifth order RK method (Butcher method). This simulation results can be used to develop an automatic photocatlytic reactor for industrial wastewater treatment. Catalyst activity decay and its effect on each batch have been incorporated in this model.

  5. The fate of arsenic adsorbed on iron oxides in the presence of arsenite-oxidizing bacteria.

    PubMed

    Zhang, Zhennan; Yin, Naiyi; Du, Huili; Cai, Xiaolin; Cui, Yanshan

    2016-05-01

    Arsenic (As) is a redox-active metalloid whose toxicity and mobility in soil depend on its oxidation state. Arsenite [As(III)] can be oxidized by microbes and adsorbed by minerals in the soil. However, the combined effects of these abiotic and biotic processes are not well understood. In this study, the fate of arsenic in the presence of an isolated As(III)-oxidizing bacterium (Pseudomonas sp. HN-1, 10(9) colony-forming units (CFUs)·ml(-1)) and three iron oxides (goethite, hematite, and magnetite at 1.6 g L(-1)) was determined using batch experiments. The total As adsorption by iron oxides was lower with bacteria present and was higher with iron oxides alone. The total As adsorption decreased by 78.6%, 36.0% and 79.7% for goethite, hematite and magnetite, respectively, due to the presence of bacteria. As(III) adsorbed on iron oxides could also be oxidized by Pseudomonas sp. HN-1, but the oxidation rate (1.3 μmol h(-1)) was much slower than the rate in the aqueous phase (96.2 μmol h(-1)). Therefore, the results of other studies with minerals only might overestimate the adsorptive capacity of solids in natural systems; the presence of minerals might hinder As(III) oxidation by microbes. Under aerobic conditions, in the presence of iron oxides and As(III)-oxidizing bacteria, arsenic is adsorbed onto iron oxides within the adsorption capacity, and As(V) is the primary form in the solid and aqueous phases. PMID:26933901

  6. A method for preparing ferric activated carbon composites adsorbents to remove arsenic from drinking water.

    PubMed

    Zhang, Qiao Li; Lin, Y C; Chen, X; Gao, Nai Yun

    2007-09-30

    Iron oxide/activated carbon (FeO/AC) composite adsorbent material, which was used to modify the coal-based activated carbon (AC) 12 x 40, was prepared by the special ferric oxide microcrystal in this study. This composite can be used as the adsorbent to remove arsenic from drinking water, and Langmuir isotherm adsorption equation well describes the experimental adsorption isotherms. Then, the arsenic desorption can subsequently be separated from the medium by using a 1% aqueous NaOH solution. The apparent characters and physical chemistry performances of FeO/AC composite were investigated by X-ray diffraction (XRD), nitrogen adsorption, scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). Batch and column adsorption experiments were carried out to investigate and compare the arsenic removal capability of the prepared FeO/AC composite material and virgin activated carbon. It can be concluded that: (1) the main phase present in this composite are magnetite (Fe(3)O(4)), maghemite (gamma-Fe(2)O(3)), hematite (alpha-Fe(2)O(3)) and goethite (alpha-FeO(OH)); (2) the presence of iron oxides did not significantly affect the surface area or the pore structure of the activated carbon; (3) the comparisons between the adsorption isotherms of arsenic from aqueous solution onto the composite and virgin activated carbon showed that the FeO/AC composite behave an excellent capacity of adsorption arsenic than the virgin activated carbon; (4) column adsorption experiments with FeO/AC composite adsorbent showed that the arsenic could be removed to below 0.01 mg/L within 1250 mL empty bed volume when influent concentration was 0.5mg/L. PMID:17434260

  7. Fabrication of a biomimetic adsorbent imprinted with a common specificity determinant for the removal of α- and β-amanitin from plasma.

    PubMed

    Tan, Lei; He, Rong; Li, Yongxian; Liang, Yong; Li, He; Tang, Youwen

    2016-08-12

    α-Amanitin and β-amanitin are the main toxins of mushroom poisoning. The application of traditional non-selective adsorbents is not satisfactory in clinical treatment of amanita mushroom poisoning due to lack of specificity adsorption capability of these adsorbents toward amanitin toxins. In the current work, we introduce a novel molecularly imprinted biomimetic adsorbent based on a ligand specificity determinant through surface imprinted strategy. Owing to the expensive price of the amanitin sources, we selected a typical common moiety of α, β-amanitin as specificity determinant to synthesize a template necessary for the preparation of molecularly imprinted polymers (MIPs). Computer simulation was used to initially select acidic methacrylic acid (MAA) and basic 4-vinyl pyridine (4-VP) together as functional monomers. The experiments further demonstrated that the synergistic interaction of MAA and 4-VP played a primary role in the recognition of α, β-amanitin by MIPs. By means of batch and packed-bed column experiment and the hemocompatibility evaluation, the resultant biomimetic adsorbent has been proved to be capable of selectively removing α, β-amanitin and possess good hemocompatibility. This novel adsorbent has great potential to find application in human plasma purification. PMID:27394089

  8. Effect of glass-batch makeup on the melting process

    SciTech Connect

    Hrma, Pavel R; Schweiger, Michael J; Humrickhouse, Carissa J; Moody, J Adam; Tate, Rachel M; Rainsdon, Timothy T; Tegrotenhuis, Nathan E; Arrigoni, Benjamin M; Marcial, Jose; Rodriguez, Carmen P; Tincher, Benjamin

    2010-03-29

    The response of a glass batch to heating is determined by the batch makeup and in turn determines the rate of melting. Batches formulated for a high-alumina nuclear waste to be vitrified in an all-electric melter were heated at a constant temperature-increase rate to determine changes in melting behavior in response to the selection of batch chemicals and silica grain-size as well as the addition of heat-generating reactants. The type of batch materials and the size of silica grains determine how much, if any, primary foam occurs during melting. Small quartz grains, 5-μm in size, caused extensive foaming because their major portion dissolved at temperatures <800°C, contributing to the formation of viscous glass-forming melt that trapped evolving batch gases. Primary foam did not occur in batches with larger quartz grains, ±75 μm in size, because their major portion dissolved at temperatures >800°C when batch gases no longer evolved. The exothermal reaction of nitrates with sucrose was ignited at a temperature as low as 160°C and caused a temporary jump in temperature of several hundred degrees. Secondary foam, the source of which is oxygen from redox reactions, occurred in all batches of a limited composition variation involving five oxides, B2O3, CaO, Li2O, MgO, and Na2O. The foam volume at the maximum volume-increase rate was a weak function of temperature and melt basicity. Neither the batch makeup nor the change in glass composition had a significant impact on the dissolution of silica grains. The impacts of primary foam generation on glass homogeneity and the rate of melting in large-scale continuous furnaces have yet to be established via mathematical modeling and melter experiments.

  9. Biodenitrification in Sequencing Batch Reactors. Final report

    SciTech Connect

    Silverstein, J.

    1996-01-23

    One plan for stabilization of the Solar Pond waters and sludges at Rocky Flats Plant (RFP), is evaporation and cement solidification of the salts to stabilize heavy metals and radionuclides for land disposal as low-level mixed waste. It has been reported that nitrate (NO{sub 3}{sub {minus}}) salts may interfere with cement stabilization of heavy metals and radionuclides. Therefore, biological nitrate removal (denitrification) may be an important pretreatment for the Solar Pond wastewaters at RFP, improving the stability of the cement final waste form, reducing the requirement for cement (or pozzolan) additives and reducing the volume of cemented low-level mixed waste requiring ultimate disposal. A laboratory investigation of the performance of the Sequencing Batch Reactor (SBR) activated sludge process developed for nitrate removal from a synthetic brine typical of the high-nitrate and high-salinity wastewaters in the Solar Ponds at Rocky Flats Plant was carried out at the Environmental Engineering labs at the University of Colorado, Boulder, between May 1, 1994 and October 1, 1995.

  10. Kinetic study of batch and fed-batch enzymatic saccharification of pretreated substrate and subsequent fermentation to ethanol

    PubMed Central

    2012-01-01

    Background Enzymatic hydrolysis, the rate limiting step in the process development for biofuel, is always hampered by its low sugar concentration. High solid enzymatic saccharification could solve this problem but has several other drawbacks such as low rate of reaction. In the present study we have attempted to enhance the concentration of sugars in enzymatic hydrolysate of delignified Prosopis juliflora, using a fed-batch enzymatic hydrolysis approach. Results The enzymatic hydrolysis was carried out at elevated solid loading up to 20% (w/v) and a comparison kinetics of batch and fed-batch enzymatic hydrolysis was carried out using kinetic regimes. Under batch mode, the actual sugar concentration values at 20% initial substrate consistency were found deviated from the predicted values and the maximum sugar concentration obtained was 80.78 g/L. Fed-batch strategy was implemented to enhance the final sugar concentration to 127 g/L. The batch and fed-batch enzymatic hydrolysates were fermented with Saccharomyces cerevisiae and ethanol production of 34.78 g/L and 52.83 g/L, respectively, were achieved. Furthermore, model simulations showed that higher insoluble solids in the feed resulted in both smaller reactor volume and shorter residence time. Conclusion Fed-batch enzymatic hydrolysis is an efficient procedure for enhancing the sugar concentration in the hydrolysate. Restricting the process to suitable kinetic regimes could result in higher conversion rates. PMID:22433563

  11. Fundamental characteristics of synthetic adsorbents intended for industrial chromatographic separations.

    PubMed

    Adachi, Tadashi; Isobe, Eiji

    2004-05-14

    With the aim of obtaining comprehensive information on the selection of synthetic adsorbents for industrial applications, effect of pore and chemical structure of industrial-grade synthetic adsorbents on adsorption capacity of several pharmaceutical compounds was investigated. For relatively low molecular mass compounds, such as cephalexin, berberine chloride and tetracycline hydrochloride, surface area per unit volume of polystyrenic adsorbents dominated the equilibrium adsorption capacity. On the contrary, effect of pore size of the polystyrenic adsorbents on the equilibrium adsorption capacity was observed for relatively high molecular mass compounds, such as rifampicin, Vitamin B12 and insulin. Polystyrenic adsorbent with high surface area and small pore size showed small adsorption capacity for relatively high molecular mass compounds, whereas polystyrenic adsorbent with relatively small surface area but with large pore size showed large adsorption capacity. Effect of chemical structure on the equilibrium adsorption capacity of several pharmaceutical compounds was also studied among polystyrenic, modified polystyrenic and polymethacrylic adsorbents. The modified polystyrenic adsorbent showed larger adsorption capacity for all compounds tested in this study due to enhanced hydrophobicity. The polymethacrylic adsorbent possessed high adsorption capacity for rifampicin and insulin, but it showed lower adsorption capacity for the other compounds studied. This result may be attributed to hydrogen bonding playing major role for the adsorption of compounds on polymethacrylic adsorbent. Furthermore, column adsorption experiments were operated to estimate the effect of pore characteristics of the polystyrenic adsorbents on dynamic adsorption behavior, and it is found that both surface area and pore size of the polystyrenic adsorbents significantly affect the dynamic adsorption capacity as well as flow rate. PMID:15139411

  12. Morphologically structured model for antitumoral retamycin production during batch and fed-batch cultivations of Streptomyces olindensis.

    PubMed

    Giudici, Reinaldo; Pamboukian, Celso R D; Facciotti, Maria Cândida R

    2004-05-20

    A morphologically structured model is proposed to describe trends in biomass growth, substrate consumption, and antitumoral retamycin production during batch and fed-batch cultivations of Streptomyces olindensis. Filamentous biomass is structured into three morphological compartments (apical, subapical, and hyphal), and the production of retamycin, a secondary metabolite, is assumed to take place in the subapical cell compartment. Model accounts for the effect of glucose as well as complex nitrogen source on both the biomass growth and retamycin production. Laboratory data from bench-scale batch and fed-batch fermentations were used to estimate some model parameters by nonlinear regression. The predictive capability of the model was then tested for additional fed-batch and continuous experiments not used in the previous fitting procedure. The model predictions show fair agreement to the experimental data. The proposed model can be useful for further studies on process optimization and control. PMID:15112294

  13. Carbonaceous adsorbent regeneration and halocarbon displacement by hydrocarbon gases

    DOEpatents

    Senum, G.I.; Dietz, R.N.

    1994-04-05

    This invention describes a process for regeneration of halocarbon bearing carbonaceous adsorbents through which a carbonaceous adsorbent is contacted with hydrocarbon gases, preferably propane, butane and pentane at near room temperatures and at atmospheric pressure. As the hydrocarbon gases come in contact with the adsorbent, the hydrocarbons displace the halocarbons by physical adsorption. As a result of using this process, the halocarbon concentration and the hydrocarbon eluant is increased thereby allowing for an easier recovery of pure halocarbons. By using the process of this invention, carbonaceous adsorbents can be regenerated by an inexpensive process which also allows for subsequent re-use of the recovered halocarbons. 8 figures.

  14. Carbonaceous adsorbent regeneration and halocarbon displacement by hydrocarbon gases

    DOEpatents

    Senum, Gunnar I.; Dietz, Russell N.

    1994-01-01

    This invention describes a process for regeneration of halocarbon bearing carbonaceous adsorbents through which a carbonaceous adsorbent is contacted with hydrocarbon gases, preferably propane, butane and pentane at near room temperatures and at atmospheric pressure. As the hydrocarbon gases come in contact with the adsorbent, the hydrocarbons displace the halocarbons by physical adsorption. As a result of using this process, the halocarbon concentration and the hydrocarbon eluant is increased thereby allowing for an easier recovery of pure halocarbons. By using the process of this invention, carbonaceous adsorbents can be regenerated by an inexpensive process which also allows for subsequent re-use of the recovered halocarbons.

  15. Video STM Studies of Adsorbate Diffusion at Electrochemical Interfaces

    NASA Astrophysics Data System (ADS)

    Tansel, T.; Magnussen, O. M.

    2006-01-01

    Direct in situ studies of the surface diffusion of isolated adsorbates at an electrochemical interface by high-speed scanning tunneling microscopy (video STM) are presented for sulfide adsorbates on Cu(100) in HCl solution. As revealed by a quantitative statistical analysis, the adsorbate motion can be described by thermally activated hopping between neighboring adsorption sites with an activation energy that increases linearly with electrode potential by 0.50 eV per V. This can be explained by changes in the adsorbate dipole moment during the hopping process and contributions from coadsorbates.

  16. Development and evaluation of Mn oxide-coated composite adsorbent for the removal and recovery of heavy metals from coal processing wastewater. Final report, December 1995

    SciTech Connect

    Fan, Huan Jung; Anderson, P.R.

    1995-12-31

    The overall objective of this research was to evaluate a Mn oxide-coated granular activated carbon (MnGAC) for the removal and recovery of metals from wastewaters. The composite adsorbent was prepared by coating M-n-oxide onto granular activated carbon. Three coating methods (adsorption, precipitation, and dry oxidation) were developed and studied in this research. The adsorbent (MnTOG) prepared by a dry oxidation method had the highest Cu(II) adsorption capacity of the three synthesis methods. In multiple adsorption/regeneration cycle tests, MnTOG had better Cu(II) removal relative to those adsorbents prepared by other methods. MnTOG had the ability to remove Cu(II) and Cd(II) to trace level (< 4 ug/L) in a column process at least through 3000 and 1400 BV, respectively. Cd(II) removal was hindered by the presence of Cu(II). However, Cu(II) removal was only slightly reduced by the presence of Cd(II). Cu(II) adsorption in batch and fixed-bed processes onto MnTOG was successfully modeled with a homogeneous surface diffusion model (HSDM). However, the HSDM could only successfully describe the adsorption of Cd(II) onto MnTOG in the batch process, but not the fixed-bed process. M-n oxide can be deposited on GAC to create a composite adsorbent with an increased Cu(II) or Cd(II) adsorption capacity. Composite adsorbent (MnGAC) has the potential to become an efficient way to remove metals from metal contaminated wastewater.

  17. Linear transport models for adsorbing solutes

    NASA Astrophysics Data System (ADS)

    Roth, K.; Jury, W. A.

    1993-04-01

    A unified linear theory for the transport of adsorbing solutes through soils is presented and applied to analyze movement of napropamide through undisturbed soil columns. The transport characteristics of the soil are expressed in terms of the travel time distribution of the mobile phase which is then used to incorporate local interaction processes. This approach permits the analysis of all linear transport processes, not only the small subset for which a differential description is known. From a practical point of view, it allows the direct use of measured concentrations or fluxes of conservative solutes to characterize the mobile phase without first subjecting them to any model. For complicated flow regimes, this may vastly improve the identification of models and estimation of their parameters for the local adsorption processes.

  18. The persistence length of adsorbed dendronized polymers

    NASA Astrophysics Data System (ADS)

    Grebikova, Lucie; Kozhuharov, Svilen; Maroni, Plinio; Mikhaylov, Andrey; Dietler, Giovanni; Schlüter, A. Dieter; Ullner, Magnus; Borkovec, Michal

    2016-07-01

    The persistence length of cationic dendronized polymers adsorbed onto oppositely charged substrates was studied by atomic force microscopy (AFM) and quantitative image analysis. One can find that a decrease in the ionic strength leads to an increase of the persistence length, but the nature of the substrate and of the generation of the side dendrons influence the persistence length substantially. The strongest effects as the ionic strength is being changed are observed for the fourth generation polymer adsorbed on mica, which is a hydrophilic and highly charged substrate. However, the observed dependence on the ionic strength is much weaker than the one predicted by the Odijk, Skolnik, and Fixman (OSF) theory for semi-flexible chains. Low-generation polymers show a variation with the ionic strength that resembles the one observed for simple and flexible polyelectrolytes in solution. For high-generation polymers, this dependence is weaker. Similar dependencies are found for silica and gold substrates. The observed behavior is probably caused by different extents of screening of the charged groups, which is modified by the polymer generation, and to a lesser extent, the nature of the substrate. For highly ordered pyrolytic graphite (HOPG), which is a hydrophobic and weakly charged substrate, the electrostatic contribution to the persistence length is much smaller. In the latter case, we suspect that specific interactions between the polymer and the substrate also play an important role.The persistence length of cationic dendronized polymers adsorbed onto oppositely charged substrates was studied by atomic force microscopy (AFM) and quantitative image analysis. One can find that a decrease in the ionic strength leads to an increase of the persistence length, but the nature of the substrate and of the generation of the side dendrons influence the persistence length substantially. The strongest effects as the ionic strength is being changed are observed for the fourth

  19. FRIT DEVELOPMENT FOR SLUDGE BATCH 6

    SciTech Connect

    Fox, K.; Edwards, T.; Zamecnik, J.

    2010-05-13

    The Savannah River National Laboratory (SRNL) evaluated a large number of Sludge Batch 6 (SB6) composition projections to support frit optimization for SB6 vitrification at the Defense Waste Processing Facility (DWPF). The evaluations discussed in this report occurred over a period of about 4 months, and included about 40 composition projections, developed by both Savannah River Remediation (SRR) and SRNL. Paper study assessments were used to evaluate the sludge composition projections with arrays of potential frit compositions using the predictive models in the DWPF Product Composition Control System (PCCS). Both nominal sludge compositions and sludge compositions with anticipated compositional variation were considered. The model predictions were used to identify candidate frit compositions for each SB6 projection and to provide some guidance to SRR on washing and blending strategies for SB6 preparation. This report presents a chronological review of this process and summarizes the findings at each stage. Following initial feedback from this work, the number of washes in Tank 51 was reduced to increase the projected sodium concentration in SB6. Analyses of predicted frit performance before and after a potential decant of Tank 40 showed that the post-decant SB6 composition would be difficult to process with any frit composition and that this scenario should be avoided. Based on the most recent SB6 projections (February 2010 SB6 composition projections developed at SRNL using the measured SB6 qualification sample composition and the revised Tank Farm washing plan), Frit 418 appears to be viable for SB6 processing at a target waste loading of 36%. A Nominal Stage PCCS Measurement Acceptability Region (MAR) assessment gave projected operating windows of 25-41% waste loading, limited by predictions of nepheline crystallization. The projected operating window is reduced to 25-38% waste loading when anticipated compositional variation is considered, again limited by

  20. Utilization of maize husk (Zea mays L.) as low-cost adsorbent in removal of iron from aqueous solution.

    PubMed

    Indah, S; Helard, D; Sasmita, A

    2016-01-01

    Adsorption of iron from aqueous solution by using maize husk (Zea mays L.) as a low-cost adsorbent was studied. Batch experiments were carried out at ambient temperature, 0.075-0.250 mm of particle size and 100 rpm of agitation speed to determine the influence of initial pH, adsorbent dose, initial concentration and contact time on the removal of iron. Langmuir and Freundlich models were applied to describe the adsorption isotherm of iron by maize husk. The results showed that optimum condition of iron removal were 4 of pH solution, 20 g/L of adsorbent dose, 10 mg/L of Fe concentration and 15 min of contact time of adsorption with 0.499 mg Fe/g maize husk of adsorption capacity. Experimental data fitted well to Langmuir's adsorption equilibrium isotherm within the concentration range studied. This study demonstrated that maize husk, which is an agricultural waste, has potential for iron removal from groundwater or other polluted waters. PMID:27332838

  1. Remediation of organic and inorganic arsenic contaminated groundwater using a nanocrystalline TiO2-based adsorbent.

    PubMed

    Jing, Chuanyong; Meng, Xiaoguang; Calvache, Edwin; Jiang, Guibin

    2009-01-01

    A nanocrystalline TiO2-based adsorbent was evaluated for the simultaneous removal of As(V), As(III), monomethylarsonic acid (MMA), and dimethylarsinic acid (DMA) in contaminated groundwater. Batch experimental results show that As adsorption followed pseudo-second order rate kinetics. The competitive adsorption was described with the charge distribution multi-site surface complexation model (CD-MUSIC). The groundwater containing an average of 329 microg L(-1) As(III), 246 microg L(-1) As(V), 151 microg L(-1) MMA, and 202 microg L(-1) DMA was continuously passed through a TiO2 filter at an empty bed contact time of 6 min for 4 months. Approximately 11,000, 14,000, and 9900 bed volumes of water had been treated before the As(III), As(V), and MMA concentration in the effluent increased to 10 microg L(-1). However, very little DMA was removed. The EXAFS results demonstrate the existence of a bidentate binuclear As(V) surface complex on spent adsorbent, indicating the oxidation of adsorbed As(III). PMID:19339086

  2. Removal of aluminium from aqueous solutions using PAN-based adsorbents: characterisation, kinetics, equilibrium and thermodynamic studies.

    PubMed

    Aly, Zaynab; Graulet, Adrien; Scales, Nicholas; Hanley, Tracey

    2014-03-01

    Economic adsorbents in bead form were fabricated and utilised for the adsorption of Al(3+) from aqueous solutions. Polyacrylonitrile (PAN) beads, PAN powder and the thermally treated PAN beads (250 °C/48 h/Ar and 600 °C/48 h/Ar-H2) were characterised using different techniques including Fourier transform infrared spectroscopy, X-ray diffraction, specific surface analysis (Brunauer-Emmett-Teller), thermogravimetric analysis as well as scanning electron microscopy. Effects of pH, contact time, kinetics and adsorption isotherms at different temperatures were investigated in batch mode experiments. Aluminium kinetic data best fit the Lagergren pseudo-second-order adsorption model indicating a one-step, surface-only, adsorption process with chemisorption being the rate limiting step. Equilibrium adsorption data followed a Langmuir adsorption model with fairly low monolayer adsorption capacities suitable for freshwater clean-up only. Various constants including thermodynamic constants were evaluated from the experimental results obtained at 20, 40 and 60 °C. Positive values of ΔH° indicated that the adsorption of Al(3+) onto all three adsorbents was endothermic with less energy input required for PAN powder compared to PAN beads and low-temperature thermally treated PAN. Negative ΔG° values indicated that the aluminium adsorption process was spontaneous for all adsorbents examined. PMID:24297464

  3. Radionuclide migration laboratory studies for validation of batch sorption data

    SciTech Connect

    Triay, I.R.; Mitchell, A.J.; Ott, M.A.

    1991-12-31

    Advective and diffusive migration experiments (within the Dynamic Transport Column Experiments and Diffusion Studies of the Yucca Mountain Site Characterization Project) involve utilizing crushed material, intact, and fractured tuff in order to test and improve (if necessary) transport models by experimentally observing the migration of sorbing and non-sorbing radionuclides on a laboratory scale. Performing a validation of the sorption data obtained with batch techniques (within the Batch Sorption Study) is an integral part of the mission of the Dynamic Transport Column Experiments and Diffusion Studies. In this paper the work scope of the radionuclide migration laboratory experiments (as they apply to validation of batch sorption data) is reviewed.

  4. SORPTION PROPERTIES OF MODEL COMPOUNDS ON C18 ADSORBENTS

    EPA Science Inventory

    The bonded silica adsorbent Bondapak-C18 was evaluated for removing organic matter from secondary sewage effluents and from solutions of pure organic compounds. The adsorbent is hydrophobic and its behavior with water samples may be erratic unless first wet with a solvent. Howeve...

  5. Development of a Desulfurization Strategy for a NOx Adsorber Catalyst

    SciTech Connect

    Tomazic, Dean

    2000-08-20

    Improve NOx regeneration calibration developed in DECSE Phase I project to understand full potential of NOx adsorber catalyst over a range of operating temperatures. Develop and demonstrate a desulfurization process to restore NOx conversion efficiency lost to sulfur contamination. Investigate effect of desulfurization process on long-term performance of the NOx adsorber catalyst.

  6. Novel Anionic Clay Adsorbents for Boiler-Blow-Down Waters Reclaim and Reuse

    SciTech Connect

    Muhammad Sahimi; Theodore Tsotsis

    2010-01-08

    Arsenic (As) and Selenium (Se) are found in water in the form of oxyanions. Relatively high concentrations of As and Se have been reported both in power plant discharges, as well as, in fresh water supplies. The International Agency for Research on Cancer currently classifies As as a group 1 chemical, that is considered to be carcinogenic to humans. In Phase I of this project we studied the adsorption of As and Se by uncalcined and calcined layered double hydroxide (LDH). The focus of the present work is a systematic study of the adsorption of As and Se by conditioned LDH adsorbents. Conditioning the adsorbent significantly reduced the Mg and Al dissolution observed with uncalcined and calcined LDH. The adsorption rates and isotherms have been investigated in batch experiments using particles of four different particle size ranges. As(V) adsorption is shown to follow a Sips-type adsorption isotherm. The As(V) adsorption rate on conditioned LDH increases with decreasing adsorbent particle size; the adsorption capacity, on the other hand, is independent of the particle size. A homogeneous surface diffusion model (HSDM) and a bi-disperse pore model (BPM) - the latter viewing the LDH particles as assemblages of microparticles and taking into account bulk diffusion in the intraparticle pore space, and surface diffusion within the microparticles themselves - were used to fit the experimental kinetic data. The HSDM estimated diffusivity values dependent on the particle size, whereas the BPM predicted an intracrystalline diffusivity, which is fairly invariant with particle size. The removal of As(V) on conditioned LDH adsorbents was also investigated in flow columns, where the impact of important solution and operational parameters such as influent As concentration, pH, sorbent particle size and flow rate were studied. An early breakthrough and saturation was observed at higher flow rates and at higher influent concentrations, whereas a decrease in the sorbent particle

  7. 11. GASFIRED CRUCIBLE FURNACES WERE USED TO MELT SMALL, BATCH ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    11. GAS-FIRED CRUCIBLE FURNACES WERE USED TO MELT SMALL, BATCH QUANTITIES OF BRONZE IN STOCKHAM'S BRASS FOUNDRY FOR THE PRODUCTION OF BRONZE VALVES, CA. 1950. - Stockham Pipe & Fittings Company, 4000 Tenth Avenue North, Birmingham, Jefferson County, AL

  8. 12. Interior view of cement and aggregate batch plant showing ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    12. Interior view of cement and aggregate batch plant showing storage bins. Photographer unknown, c. 1926. Source: Ralph Pleasant. - Waddell Dam, On Agua Fria River, 35 miles northwest of Phoenix, Phoenix, Maricopa County, AZ

  9. Groundwater arsenic remediation using zerovalent iron: Batch and column tests

    EPA Science Inventory

    Recently, increasing efforts have been made to explore the applicability and limitations of zerovalent iron (Fe0) for the treatment of arsenicbearing groundwater and wastewater. The experimental batch and column tests have demonstrated that arsenate and arsenite are removed effec...

  10. 19. Main deck just forward of fish batch, portion of ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    19. Main deck just forward of fish batch, portion of fish hatch cover has been opened to show the ventilation grate below. - Schooner "Lettie G. Howard", South Street Seaport Museum, New York County, NY

  11. 1. EXTERIOR VIEW LOOKING NORTHWEST AT BATCH FURNACE BUILDING, 22' ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. EXTERIOR VIEW LOOKING NORTHWEST AT BATCH FURNACE BUILDING, 22' BAR MILL BUILDING, AND 22 BAR MILL MOTOR ROOM. - U.S. Steel Duquesne Works, 22-Inch Bar Mill, Along Monongahela River, Duquesne, Allegheny County, PA

  12. 21 CFR 111.255 - What is the requirement to establish a batch production record?

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... MANUFACTURING, PACKAGING, LABELING, OR HOLDING OPERATIONS FOR DIETARY SUPPLEMENTS Production and Process Control... relating to the production and control of each batch; (c) Your batch production record must...

  13. 21 CFR 111.255 - What is the requirement to establish a batch production record?

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... MANUFACTURING, PACKAGING, LABELING, OR HOLDING OPERATIONS FOR DIETARY SUPPLEMENTS Production and Process Control... relating to the production and control of each batch; (c) Your batch production record must...

  14. Kinetic study of lead adsorption to composite biopolymer adsorbent

    SciTech Connect

    Seki, H.; Suzuki, A.

    1999-03-15

    A kinetic study of lead adsorption to composite biopolymer adsorbents was carried out. Spherical and membranous adsorbents containing two biopolymers, humic acid and alginic acid, were used for lead adsorption in dilute acidic solutions. The shrinking core model derived by M.G. Rao and A.K. Gupta was applied to describe the rate process of lead adsorption to spherical adsorbents (average radii of 0.12, 0.15, and 0.16 cm). Furthermore, the shrinking core model was modified and adapted for description of the rate process of lead adsorption to membranous adsorbent (average thickness of 0.0216 cm). The adsorption rate process for both the cases was well described and average apparent lead diffusion coefficients of about 6 {times} 10{sup {minus}6} and 7 {times} 10{sup {minus}6} cm{sup 2}/s were found for the spherical and membranous adsorbents, respectively.

  15. Structure and properties of water film adsorbed on mica surfaces

    NASA Astrophysics Data System (ADS)

    Zhao, Gutian; Tan, Qiyan; Xiang, Li; Cai, Di; Zeng, Hongbo; Yi, Hong; Ni, Zhonghua; Chen, Yunfei

    2015-09-01

    The structure profiles and physical properties of the adsorbed water film on a mica surface under conditions with different degrees of relative humidity are investigated by a surface force apparatus. The first layer of the adsorbed water film shows ice-like properties, including a lattice constant similar with ice crystal, a high bearing capacity that can support normal pressure as high as 4 MPa, a creep behavior under the action of even a small normal load, and a character of hydrogen bond. Adjacent to the first layer of the adsorbed water film, the water molecules in the outer layer are liquid-like that can flow freely under the action of external loads. Experimental results demonstrate that the adsorbed water layer makes the mica surface change from hydrophilic to weak hydrophobic. The weak hydrophobic surface may induce the latter adsorbed water molecules to form water islands on a mica sheet.

  16. Kinetic Study of Lead Adsorption to Composite Biopolymer Adsorbent.

    PubMed

    Seki; Suzuki

    1999-03-15

    A kinetic study of lead adsorption to composite biopolymer adsorbents was carried out. Spherical and membranous adsorbents containing two biopolymers, humic acid and alginic acid, were used for lead adsorption in dilute acidic solutions. The shrinking core model derived by M. G. Rao and A. K. Gupta (Chem. Eng. J. 24, 181, 1982) was applied to describe the rate process of lead adsorption to spherical adsorbents (average radii of 0.12, 0.15, and 0.16 cm). Furthermore, the shrinking core model was modified and adapted for description of the rate process of lead adsorption to membranous adsorbent (average thickness of 0.0216 cm). The adsorption rate process for the both cases was well described and average apparent lead diffusion coefficients of about 6 x 10(-6) and 7 x 10(-6) cm2 s-1 were found for the spherical and membranous adsorbents, respectively. Copyright 1999 Academic Press. PMID:10049553

  17. Nuclear criticality safety evaluation DWPF melter -- Batch 1

    SciTech Connect

    Williamson, T.G.

    1993-12-01

    The Savannah River Site (SRS) High Level Nuclear Waste will be vitrified in the Defense Waste Processing Facility (DWPF) for long term storage and disposal. This is a preliminary safety evaluation for the Melt Cell of the DWPF vitrification process for Batch 1 waste. This evaluation demonstrates that the material in the Melt cell remains subcritical for the contents of Batch 1 which contains uranium with less than 1% by weight U-235.

  18. OPLS in batch monitoring - Opens up new opportunities.

    PubMed

    Souihi, Nabil; Lindegren, Anders; Eriksson, Lennart; Trygg, Johan

    2015-02-01

    In batch statistical process control (BSPC), data from a number of "good" batches are used to model the evolution (trajectory) of the process and they also define model control limits, against which new batches may be compared. The benchmark methods used in BSPC include partial least squares (PLS) and principal component analysis (PCA). In this paper, we have used orthogonal projections to latent structures (OPLS) in BSPC and compared the results with PLS and PCA. The experimental study used was a batch hydrogenation reaction of nitrobenzene to aniline characterized by both UV spectroscopy and process data. The key idea is that OPLS is able to separate the variation in data that is correlated to the process evolution (also known as 'batch maturity index') from the variation that is uncorrelated to process evolution. This separation of different types of variations can generate different batch trajectories and hence lead to different established model control limits to detect process deviations. The results demonstrate that OPLS was able to detect all process deviations and provided a good process understanding of the root causes for these deviations. PCA and PLS on the other hand were shown to provide different interpretations for several of these process deviations, or in some cases they were unable to detect actual process deviations. Hence, the use of OPLS in BSPC can lead to better fault detection and root cause analysis as compared to existing benchmark methods and may therefore be used to complement the existing toolbox. PMID:25604817

  19. [Characteristic of Particulate Emissions from Concrete Batching in Beijing].

    PubMed

    Xue, Yi-feng; Zhou, Zhen; Zhong, Lian-hong; Yan, Jing; Qu, Song; Huang, Yu-hu; Tian, He- zhong; Pan, Tao

    2016-01-15

    With the economic development and population growth in Beijing, there is a strong need for construction and housing, which leads to the increase of the construction areas. Meanwhile, as a local provided material, the production of concrete has been raised. In the process of concrete production by concrete batching, there are numerous particulates emitted, which have large effect on the atmospheric environment, however, systematic study about the tempo-spatial characteristics of pollutant emission from concrete batching is still rare. In this study, we estimated the emission of particulates from concrete batching from 1991 to 2012 using emission factor method, analyzed the tempo-spatial characteristics of pollutant emission, established the uncertainty range by adopting Monte-Carlo method, and predicted the future emission in 2020 based on the relative environmental and economical policies. The results showed that: (1) the emissions of particulates from concrete batching showed a trend of "first increase and then decrease", reaching the maximum in 2005, and then decreased due to stricter emission standard and enhanced environmental management. (2) according to spatial distribution, the emission of particulates from concrete batch mainly concentrated in the urban area with more human activities, and the area between the fifth ring and the sixth ring contributed the most. (3) through scenarios analysis, for further reducing the emission from concrete batching in 2020, more stricter standard for green production as well as powerful supervision is needed. PMID:27078945

  20. Milestone Report - Complete New Adsorbent Materials for Marine Testing to Demonstrate 4.5 g-U/kg Adsorbent

    SciTech Connect

    Janke, Christopher James; Das, Sadananda; Oyola, Yatsandra; Mayes, Richard T.; Saito, Tomonori; Brown, Suree; Gill, Gary; Kuo, Li-Jung; Wood, Jordana

    2014-08-01

    This report describes work on the successful completion of Milestone M2FT-14OR03100115 (8/20/2014) entitled, “Complete new adsorbent materials for marine testing to demonstrate 4.5 g-U/kg adsorbent”. This effort is part of the Seawater Uranium Recovery Program, sponsored by the U.S. Department of Energy, Office of Nuclear Energy, and involved the development of new adsorbent materials at the Oak Ridge National Laboratory (ORNL) and marine testing at the Pacific Northwest National Laboratory (PNNL). ORNL has recently developed two new families of fiber adsorbents that have demonstrated uranium adsorption capacities greater than 4.5 g-U/kg adsorbent after marine testing at PNNL. One adsorbent was synthesized by radiation-induced graft polymerization of itaconic acid and acrylonitrile onto high surface area polyethylene fibers followed by amidoximation and base conditioning. This fiber showed a capacity of 4.6 g-U/kg adsorbent in marine testing at PNNL. The second adsorbent was prepared by atom-transfer radical polymerization of t-butyl acrylate and acrylonitrile onto halide-functionalized round fibers followed by amidoximation and base hydrolysis. This fiber demonstrated uranium adsorption capacity of 5.4 g-U/kg adsorbent in marine testing at PNNL.

  1. Online batch scheduling of equal-length jobs on two identical batch machines to maximise the number of early jobs

    NASA Astrophysics Data System (ADS)

    Li, Wenjie; Li, Shisheng

    2015-03-01

    We study the online batch scheduling of equal-length jobs on two identical batch machines. Each batch machine can process up to b jobs simultaneously as a batch (where b is called the capacity of the machines). The goal is to determine a schedule that maximises the (weighted) number of early jobs. For the non-preemptive model, we first present an upper bound that depends on the machine capacity b, and then we provide a greedy online algorithm with a competitive ratio of 1/(b + 1). For the preemption-restart model with b = ∞, we first show that no online algorithm has a competitive ratio greater than 0.595, and then we design an online algorithm with a competitive ratio of ?.

  2. Imaging the wave functions of adsorbed molecules

    PubMed Central

    Lüftner, Daniel; Ules, Thomas; Reinisch, Eva Maria; Koller, Georg; Soubatch, Serguei; Tautz, F. Stefan; Ramsey, Michael G.; Puschnig, Peter

    2014-01-01

    The basis for a quantum-mechanical description of matter is electron wave functions. For atoms and molecules, their spatial distributions and phases are known as orbitals. Although orbitals are very powerful concepts, experimentally only the electron densities and -energy levels are directly observable. Regardless whether orbitals are observed in real space with scanning probe experiments, or in reciprocal space by photoemission, the phase information of the orbital is lost. Here, we show that the experimental momentum maps of angle-resolved photoemission from molecular orbitals can be transformed to real-space orbitals via an iterative procedure which also retrieves the lost phase information. This is demonstrated with images obtained of a number of orbitals of the molecules pentacene (C22H14) and perylene-3,4,9,10-tetracarboxylic dianhydride (C24H8O6), adsorbed on silver, which are in excellent agreement with ab initio calculations. The procedure requires no a priori knowledge of the orbitals and is shown to be simple and robust. PMID:24344291

  3. Mesoporous carbon nanomaterials as environmental adsorbents.

    PubMed

    Tripathi, Pranav K; Gan, Lihua; Liu, Mingxian; Rao, Nageswara N

    2014-02-01

    The transportation and diffusion of the guest objects or molecules in the porous carbon nanomaterials can be facilitated by reducing the pathway and resistance. The reduced pathway depends on the porous nature of carbon nanomaterials. Classification of porous carbon materials by the International Union of Pure and Applied Chemistry (IUPAC) has given a new opportunity to design the pores as per their applicability and to understand the mobility of ions, atoms, and molecules in the porous network of carbon materials and also advanced their countless applicability. However, synthesis of carbon nanomaterials with a desired porous network is still a great challenge. Although, remarkable developments have taken place in the recent years, control over the pores size and/or hierarchical porous architectures, especially in the synthesis of carbon nanospheres (CNSs) and ordered mesoporous carbon (OMCs) is still intriguing. The micro and mesoporous CNSs and OMCs have been prepared by a variety of procedures and over a wide range of compositions using various different surfactant templates and carbon precursors etc. The mechanisms of formation of micromesopore in the CNSs and OMCs are still evolving. On the other hand, the urge for adsorbents with very high adsorption capacities for removing contaminants from water is growing steadily. In this review, we address the state-of-the-art synthesis of micro and mesoporous CNSs and OMCs, giving examples of their applications for adsorptive removals of contaminants including our own research studies. PMID:24749459

  4. NASA Applications of Molecular Adsorber Coatings

    NASA Technical Reports Server (NTRS)

    Abraham, Nithin S.

    2015-01-01

    The Molecular Adsorber Coating (MAC) is a new, innovative technology that was developed to reduce the risk of molecular contamination on spaceflight applications. Outgassing from materials, such as plastics, adhesives, lubricants, silicones, epoxies, and potting compounds, pose a significant threat to the spacecraft and the lifetime of missions. As a coating made of highly porous inorganic materials, MAC offers impressive adsorptive capabilities that help capture and trap contaminants. Past research efforts have demonstrated the coating's promising adhesion performance, optical properties, acoustic durability, and thermal stability. These results advocate its use near or on surfaces that are targeted by outgassed materials, such as internal optics, electronics, detectors, baffles, sensitive instruments, thermal control coatings, and vacuum chamber test environments. The MAC technology has significantly progressed in development over the recent years. This presentation summarizes the many NASA spaceflight applications of MAC and how the coatings technology has been integrated as a mitigation tool for outgassed contaminants. For example, this sprayable paint technology has been beneficial for use in various vacuum chambers for contamination control and hardware bake-outs. The coating has also been used in small instrument cavities within spaceflight instrument for NASA missions.

  5. Morphological characterization of furfuraldehyde resins adsorbents

    SciTech Connect

    Sanchez, R.; Monteiro, S.N.; D`Almeida, J.R.

    1996-12-31

    Sugar cane is one of the most traditional plantation cultivated crops in large areas in Brazil. The State University of the North of Rio de Janeiro, UENF, is currently engaged in a program aimed to exploit the potentialities of sugar cane industry as a self sustained non-polluting enterprise. One of the projects being carried out at the UENF is the transformation of sugar cane bagasse in precursor materials for the industry of furan derivatives such as the furfuraldehyde resins obtained by acid catalysis. The possibility of employing acid catalyzed furfuraldehyde resins as selective adsorbents has arisen during a comprehensive study of physical-chemical adsorption properties of these materials. The morphology of these resins depend on the synthesis method. Scanning Electron Microscopic studies of these materials which were synthesized, in bulk (FH-M) and solution (FH-D), showed differences in surface density and particle size. Using mercury porosimeter techniques and BET adsorption methods, it was found different pore size distributions and a decrement in surface area when solvent was employed in the synthesis process. By thermogravimetric analysis it was found similar weight losses (6%) of water adsorption and a small differences in thermal stabilities.

  6. Selective recovery of minor trivalent actinides from high level liquid waste by R-BTP/SiO2-P adsorbents

    NASA Astrophysics Data System (ADS)

    Sano, Yuichi; Surugaya, Naoki; Yamamoto, Masahiko

    2010-03-01

    Concerning the selective recovery of minor trivalent actinides (MA(III) = Am(III) and Cm(III)) from high level liquid waste (HLLW) by extraction chromatography, adsorption and elution behaviours of MA(III) and fission products (FP) in a nitric acid media were studied using iHex-BTP/SiO2-P adsorbents, which is expected to show high adsorption affinity for MA(III) even in concentrated HNO3 solution, such as HLLW. In the batch experiments, Pd showed strong adsorption on iHex-BTP/SiO2-P adsorbents under any concentration of HNO3. The MA(III) and heavy Ln(III) (Sm(III), Eu(III) and Gd(III)) were also adsorbed at the condition of high HNO3 concentration, but they showed no adsorption under low HNO3concentration. The separation factor for MA(III)/heavy Ln(III) took the maximum value (over 100) at around 1mol/dm3 HNO3. It was difficult to elute MA(III) or heavy Ln(III) selectively by HNO3 from the iHex-BTP/SiO2-P adsorbents degradated by γ-ray irradiation. The chromatographic separation of real HLLW by an iHex-BTP/SiO2-P column showed that MA(III) could be recovered selectively by adjusting the acidity of the feed solution, i.e. HLLW, to 1mol/dm3 and using H2O as eluant. The adsorption of Pd(II) can be decreased by the addition of appropriate complexing reagents, e.g. DTPA, into HLLW without any effects on the MA(III) adsorption.

  7. A high-fidelity batch simulation environment for integrated batch and piloted air combat simulation analysis

    NASA Technical Reports Server (NTRS)

    Goodrich, Kenneth H.; Mcmanus, John W.; Chappell, Alan R.

    1992-01-01

    A batch air combat simulation environment known as the Tactical Maneuvering Simulator (TMS) is presented. The TMS serves as a tool for developing and evaluating tactical maneuvering logics and to evaluate the tactical implications of perturbations to aircraft performance or supporting systems. The TMS is capable of simulating air combat between any number of engagement participants, with practical limits imposed by computer memory and processing power. Aircraft are modeled using equations of motion, control laws, aerodynamics and propulsive characteristics, and databases representative of a modern high-performance aircraft with and without thrust-vectoring capability are included. A Tactical Autopilot is implemented in the aircraft simulation model to convert guidance commands issued by computerized maneuvering logics in the form of desired angle-of-attack and wind axis-bank angle into inputs to the inner-loop control augmentation system of the aircraft.

  8. SLUDGE BATCH 7B GLASS VARIABILITY STUDY

    SciTech Connect

    Johnson, F.; Edwards, T.

    2011-10-25

    The Defense Waste Processing Facility (DWPF) is preparing to initiate processing Sludge Batch 7b (SB7b). In support of the upcoming processing, the Savannah River National Laboratory (SRNL) provided a recommendation to utilize Frits 418 with a 6% Na{sub 2}O addition (26 wt% Na{sub 2}O in sludge) and 702 with a 4% Na{sub 2}O addition (24 wt% Na{sub 2}O in sludge) to process SB7b. This recommendation was based on assessments of the compositional projections for SB7b available at the time from the Savannah River Remediation (SRR). To support qualification of SB7b, SRNL executed a variability study to assess the applicability of the current durability models for SB7b. The durability models were assessed over the expected composition range of SB7b, including potential caustic additions, combined with Frits 702 and 418 over a 32-40% waste loading (WL) range. Thirty four glasses were selected based on Frits 418 and 702 coupled with the sludge projections with an additional 4-6% Na{sub 2}O to reflect the potential caustic addition. Six of these glasses, based on average nominal sludge compositions including the appropriate caustic addition, were developed for both Frit 418 and Frit 702 at 32, 36 and 40% WL to provide coverage in the center of the anticipated SB7b glass region. All glasses were fabricated and characterized using chemical composition analysis, X-ray diffraction (XRD) and the Product Consistency Test (PCT). To comply with the DWPF Glass Product Control Program, a total of thirty four glasses were fabricated to assess the applicability of the current DWPF PCCS durability models. Based on the measured PCT response, all of the glasses were acceptable with respect to the Environmental Assessment (EA) benchmark glass regardless of thermal history. The NL[B] values of the SB7b variability study glasses were less than 1.99 g/L as compared to 16.695 g/L for EA. A small number of the D-optimally selected 'outer layer' extreme vertices (EV) glasses were not predictable

  9. SLUDGE BATCH VARIABILITY STUDY WITH FRIT 418

    SciTech Connect

    Johnson, F.; Edwards, T.

    2010-11-29

    The Defense Waste Processing Facility (DWPF) initiated processing Sludge Batch 6 (SB6) in the summer of 2010. In support of processing, the Savannah River National Laboratory (SRNL) provided a recommendation to utilize Frit 418 to process SB6. This recommendation was based on assessments of the compositional projections for SB6 available at the time from the Liquid Waste Organization (LWO) and SRNL (using a model-based approach). To support qualification of SB6, SRNL executed a variability study to assess the applicability of the current durability models for SB6. The durability models were assessed over the expected Frit 418-SB6 composition range. Seventeen glasses were selected for the variability study based on the sludge projections used in the frit recommendation. Five of the glasses are based on the centroid of the compositional region, spanning a waste loading (WL) range of 32 to 40%. The remaining twelve glasses are extreme vertices (EVs) of the sludge region of interest for SB6 combined with Frit 418 and are all at 36% WL. These glasses were fabricated and characterized using chemical composition analysis, X-ray diffraction (XRD) and the Product Consistency Test (PCT). After initiating the SB6 variability study, the measured composition of the SB6 Tank 51 qualification glass produced at the SRNL Shielded Cells Facility indicated that thorium was present in the glass at an appreciable concentration (1.03 wt%), which made it a reportable element for SB6. This concentration of ThO{sub 2} resulted in a second phase of experimental studies. Five glasses were formulated that were based on the centroid of the new sludge compositional region combined with Frit 418, spanning a WL range of 32 to 40%. These glasses were fabricated and characterized using chemical composition analysis and the PCT. Based on the measured PCT response, all of the glasses (with and without thorium) were acceptable with respect to the Environmental Assessment (EA) reference glass

  10. Butanol production by immobilised Clostridium acetobutylicum in repeated batch, fed-batch, and continuous modes of fermentation.

    PubMed

    Dolejš, Igor; Krasňan, Vladimír; Stloukal, Radek; Rosenberg, Michal; Rebroš, Martin

    2014-10-01

    Clostridium acetobutylicum immobilised in polyvinylalcohol, lens-shaped hydrogel capsules (LentiKats(®)) was studied for production of butanol and other products of acetone-butanol-ethanol fermentation. After optimising the immobilisation protocol for anaerobic bacteria, continuous, repeated batch, and fed-batch fermentations in repeated batch mode were performed. Using glucose as a substrate, butanol productivity of 0.41 g/L/h and solvent productivity of 0.63 g/L/h were observed at a dilution rate of 0.05 h(-1) during continuous fermentation with a concentrated substrate (60 g/L). Through the process of repeated batch fermentation, the duration of fermentation was reduced from 27.8h (free-cell fermentation) to 3.3h (immobilised cells) with a solvent productivity of 0.77 g/L/h (butanol 0.57 g/L/h). The highest butanol and solvent productivities of 1.21 and 1.91 g/L/h were observed during fed-batch fermentation operated in repeated batch mode with yields of butanol (0.15 g/g) and solvents (0.24 g/g), respectively, produced per gram of glucose. PMID:25108474

  11. Batch and Pulsed Fed-Batch Cultures of Aspergillus flavipes FP-500 Growing on Lemon Peel at Stirred Tank Reactor.

    PubMed

    Wolf-Márquez, V E; García-García, E; García-Rivero, M; Aguilar-Osorio, G; Martínez Trujillo, M A

    2015-11-01

    Aspergillus flavipes FP-500 grew up on submerged cultures using lemon peel as the only carbon source, developing several batch and pulsed fed-batch trials on a stirred tank reactor. The effect of carbon source concentration, reducing sugar presence and initial pH on exopectinase and endopectinase production, was analyzed on batch cultures. From this, we observed that the highest substrate concentration favored biomass (X max) but had not influence on the corresponding specific production (q p) of both pectinases; the most acid condition provoked higher endopectinase-specific productions but had not a significant effect on those corresponding to exopectinases; and reducing sugar concentrations higher than 1.5 g/L retarded pectinase production. On the other hand, by employing the pulsed fed-batch operation mode, we observed a prolonged growth phase, and an increase of about twofold on endopectinase production without a significant raise on biomass concentration. So, pulsed fed-batch seems to be a good alternative for obtaining higher endopectinase titers by using high lemon peel quantities without having mixing and repression problems to the system. The usefulness of unstructured kinetic models for explaining, under a theoretic level, the behavior of the fungus along the batch culture with regard to pectinase production was evident. PMID:26304128

  12. Carbon dioxide pressure swing adsorption process using modified alumina adsorbents

    DOEpatents

    Gaffney, Thomas Richard; Golden, Timothy Christopher; Mayorga, Steven Gerard; Brzozowski, Jeffrey Richard; Taylor, Fred William

    1999-01-01

    A pressure swing adsorption process for absorbing CO.sub.2 from a gaseous mixture containing CO.sub.2 comprising introducing the gaseous mixture at a first pressure into a reactor containing a modified alumina adsorbent maintained at a temperature ranging from 100.degree. C. and 500.degree. C. to adsorb CO.sub.2 to provide a CO.sub.2 laden alumina adsorbent and a CO.sub.2 depleted gaseous mixture and contacting the CO.sub.2 laden adsorbent with a weakly adsorbing purge fluid at a second pressure which is lower than the first pressure to desorb CO.sub.2 from the CO.sub.2 laden alumina adsorbent. The modified alumina adsorbent which is formed by depositing a solution having a pH of 3.0 or more onto alumina and heating the alumina to a temperature ranging from 100.degree. C. and 600.degree. C., is not degraded by high concentrations of water under process operating conditions.

  13. Carbon dioxide pressure swing adsorption process using modified alumina adsorbents

    DOEpatents

    Gaffney, T.R.; Golden, T.C.; Mayorga, S.G.; Brzozowski, J.R.; Taylor, F.W.

    1999-06-29

    A pressure swing adsorption process for absorbing CO[sub 2] from a gaseous mixture containing CO[sub 2] comprises introducing the gaseous mixture at a first pressure into a reactor containing a modified alumina adsorbent maintained at a temperature ranging from 100 C and 500 C to adsorb CO[sub 2] to provide a CO[sub 2] laden alumina adsorbent and a CO[sub 2] depleted gaseous mixture and contacting the CO[sub 2] laden adsorbent with a weakly adsorbing purge fluid at a second pressure which is lower than the first pressure to desorb CO[sub 2] from the CO[sub 2] laden alumina adsorbent. The modified alumina adsorbent which is formed by depositing a solution having a pH of 3.0 or more onto alumina and heating the alumina to a temperature ranging from 100 C and 600 C, is not degraded by high concentrations of water under process operating conditions. 1 fig.

  14. From adsorption to condensation: the role of adsorbed molecular clusters.

    PubMed

    Yaghoubian, Sima; Zandavi, Seyed Hadi; Ward, C A

    2016-08-01

    The adsorption of heptane vapour on a smooth silicon substrate with a lower temperature than the vapour is examined analytically and experimentally. An expression for the amount adsorbed under steady state conditions is derived from the molecular cluster model of the adsorbate that is similar to the one used to derive the equilibrium Zeta adsorption isotherm. The amount adsorbed in each of a series of steady experiments is measured using a UV-vis interferometer, and gives strong support to the amount predicted to be adsorbed. The cluster distribution is used to predict the subcooling temperature required for the adsorbed vapour to make a disorder-order phase transition to become an adsorbed liquid, and the subcooling temperature is found to be 2.7 ± 0.4 K. The continuum approach for predicting the thickness of the adsorbed liquid film originally developed by Nusselt is compared with that measured and is found to over-predict the thickness by three-orders of magnitude. PMID:27426944

  15. Methane Recovery from Gaseous Mixtures Using Carbonaceous Adsorbents

    NASA Astrophysics Data System (ADS)

    Buczek, Bronisław

    2016-06-01

    Methane recovery from gaseous mixtures has both economical and ecological aspect. Methane from different waste gases like mine gases, nitrogenated natural gases and biogases can be treated as local source for production electric and heat energy. Also occurs the problem of atmosphere pollution with methane that shows over 20 times more harmful environmental effect in comparison to carbon dioxide. One of the ways utilisation such gases is enrichment of methane in the PSA technique, which requires appropriate adsorbents. Active carbons and carbon molecular sieve produced by industry and obtained in laboratory scale were examined as adsorbent for methane recuperation. Porous structure of adsorbents was investigated using densimetry measurements and adsorption of argon at 77.5K. On the basis of adsorption data, the Dubinin-Radushkevich equation parameters, micropore volume (Wo) and characteristics of energy adsorption (Eo) as well as area micropores (Smi) and BET area (SBET) were determined. The usability of adsorbents in enrichment of the methane was evaluated in the test, which simulate the basic stages of PSA process: a) adsorbent degassing, b) pressure raise in column by feed gas, c) cocurrent desorption with analysis of out flowing gas. The composition of gas phase was accepted as the criterion of the suitability of adsorbent for methane separation from gaseous mixtures. The relationship between methane recovery from gas mixture and texture parameters of adsorbents was found.

  16. Mercury adsorption properties of sulfur-impregnated adsorbents

    USGS Publications Warehouse

    Hsi, N.-C.; Rood, M.J.; Rostam-Abadi, M.; Chen, S.; Chang, R.

    2002-01-01

    Carbonaceous and noncarbonaceous adsorbents were impregnated with elemental sulfur to evaluate the chemical and physical properties of the adsorbents and their equilibrium mercury adsorption capacities. Simulated coal combustion flue gas conditions were used to determine the equilibrium adsorption capacities for Hg0 and HgCl2 gases to better understand how to remove mercury from gas streams generated by coal-fired utility power plants. Sulfur was deposited onto the adsorbents by monolayer surface deposition or volume pore filling. Sulfur impregnation increased the total sulfur content and decreased the total and micropore surface areas and pore volumes for all of the adsorbents tested. Adsorbents with sufficient amounts of active adsorption sites and sufficient microporous structure had mercury adsorption capacities up to 4,509 ??g Hg/g adsorbent. Elemental sulfur, organic sulfur, and sulfate were formed on the adsorbents during sulfur impregnation. Correlations were established with R2>0.92 between the equilibrium Hg0/HgCl2 adsorption capacities and the mass concentrations of elemental and organic sulfur. This result indicates that elemental and organic sulfur are important active adsorption sites for Hg0 and HgCl2.

  17. Nanocellulose/nanobentonite composite anchored with multi-carboxyl functional groups as an adsorbent for the effective removal of Cobalt(II) from nuclear industry wastewater samples.

    PubMed

    Anirudhan, T S; Deepa, J R; Christa, J

    2016-04-01

    A novel adsorbent, poly(itaconic acid/methacrylic acid)-grafted-nanocellulose/nanobentonite composite [P(IA/MAA)-g-NC/NB] with multi carboxyl functional groups for the effective removal of Cobalt(II) [Co(II)] from aqueous solutions. The adsorbent was characterized using FTIR, XRD, SEM-EDS, AFM and potentiometric titrations before and after adsorption of Co(II) ions. FTIR spectra revealed that Co(II) adsorption on to the polymer may be due to the involvement of COOH groups. The surface morphological changes were observed by the SEM images. The pH was optimized as 6.0. An adsorbent dose of 2.0g/L found to be sufficient for the complete removal of Co(II) from 100mg/L at room temperature. Pseudo-first-order and pseudo-second-order models were tested to describe kinetic data and adsorption of Co(II) follows pseudo-second-order model. The equilibrium attained at 120min. Isotherm studies were conducted and data were analyzed using Langmuir, Freundlich and Sips isotherm models and best fit was Sips model. Thermodynamic study confirmed endothermic and physical nature of adsorption of the Co(II) onto the adsorbent. Desorption experiments were done with 0.1MHCl proved that without significant loss in performance adsorbent could be reused for six cycles. The practical efficacy and effectiveness of the adsorbent were tested using nuclear industrial wastewater. A double stage batch adsorption system was designed from the adsorption isotherm data of Co(II) by constructing operating lines. PMID:26844393

  18. Novel adhesive properties of poly(ethylene-oxide) adsorbed nanolayers

    NASA Astrophysics Data System (ADS)

    Zeng, Wenduo

    Solid-polymer interfaces play crucial roles in the multidisciplinary field of nanotechnology and are the confluence of physics, chemistry, biology, and engineering. There is now growing evidence that polymer chains irreversibly adsorb even onto weakly attractive solid surfaces, forming a nanometer-thick adsorbed polymer layer ("adsorbed polymer nanolayers"). It has also been reported that the adsorbed layers greatly impact on local structures and properties of supported polymer thin films. In this thesis, I aim to clarify adhesive and tribological properties of adsorbed poly(ethylene-oxide) (PEO) nanolayers onto silicon (Si) substrates, which remain unsolved so far. The adsorbed nanolayers were prepared by the established protocol: one has to equilibrate the melt or dense solution against a solid surface; the unadsorbed chains can be then removed by a good solvent, while the adsorbed chains are assumed to maintain the same conformation due to the irreversible freezing through many physical solid-segment contacts. I firstly characterized the formation process and the surface/film structures of the adsorbed nanolayers by using X-ray reflectivity, grazing incidence X-ray diffraction, and atomic force microscopy. Secondly, to compare the surface energy of the adsorbed layers with the bulk, static contact angle measurements with two liquids (water and glycerol) were carried out using a optical contact angle meter equipped with a video camera. Thirdly, I designed and constructed a custom-built adhesion-testing device to quantify the adhesive property. The experimental results provide new insight into the microscopic structure - macroscopic property relationship at the solid-polymer interface.

  19. Use of sepiolite as an adsorbent for the removal of copper (II) from industrial waste leachate

    NASA Astrophysics Data System (ADS)

    Gamze Turan, N.; Ardali, Yüksel

    2013-04-01

    as talc, but it has discontinuities and inversion of the silica sheets, which give rise to structural tunnels and blocks. In the inner blocks, all corners of the silica tetrahedral are connected to adjacent blocks, but in the outer blocks, some of the corners are Si atoms bound to hydroxyls (Si-OH). This unique structure allows the penetration of organic and inorganic species into the structure and assigns sepiolite an industrial importance in adsorption. The objective of the present study is to investigate the feasibility of using sepiolite for the adsorptive removal of Cu (II) from the industrial waste leachate. The adsorption capacities and sorption efficiencies are determined. The pseudo first order, the pseudo-second order, Elovich and the intra particle diffusion kinetic models are used to describe the kinetic data to estimate the rate constants. The adsorption of Cu (II) from the aqueous leachate of industrial wastes onto sepiolite was performed using a batch equilibrium technique. At first stage, one-factor-at-a-time experiments were performed to see the individual effects of initial pH, adsorbent dosage and contact time. The adsorption of Cu (II) was favorably influenced by an increase in the adsorbent dosage. The maximum percent removal of Cu (II) were observed at pH>6, and significantly decreased at lower pH value. The optimum contact time is found as 10 min. for the removal of Cu (II). The increment in contact time from 10 min. to 120 min. did not show a significant effect on efficiency. The maximum Cu (II) adsorption efficiencies were obtained at 94.45%. The pseudo second order kinetic model agrees very well with the dynamical behavior for the adsorption of Cu (II) from aqueous leachate of industrial waste onto sepiolite. The results indicate that the use of sepiolite that is locally available and almost free of cost as an adsorbent could be a viable alternative to activated carbon for the removal of Cu (II) ions from aqueous solutions.

  20. Batch and fixed-bed adsorption of tartrazine azo-dye onto activated carbon prepared from apricot stones

    NASA Astrophysics Data System (ADS)

    Albroomi, H. I.; Elsayed, M. A.; Baraka, A.; Abdelmaged, M. A.

    2016-02-01

    This work describes the potential of utilizing prepared activated carbon from apricot stones as an efficient adsorbent material for tartrazine (TZ) azo-dye removal in a batch and dynamic adsorption system. The results revealed that activated carbons with well-developed surface area (774 m2/g) and pore volume (1.26 cm3/g) can be manufactured from apricot stones by H3PO4 activation. In batch experiments, effects of the parameters such as initial dye concentration and temperature on the removal of the dye were studied. Equilibrium was achieved in 120 min. Adsorption capacity was found to be dependent on the initial concentration of dye solution, and maximum adsorption was found to be 76 mg/g at 100 mg/L of TZ. The adsorption capacity at equilibrium (q e) increased from 22.6 to 76 mg/g with an increase in the initial dye concentrations from 25 to 100 mg/L. The thermodynamic parameters such as change in free energy (ΔG 0), enthalpy (ΔH 0) and entropy (ΔS 0) were determined and the positive value of (ΔH) 78.1 (K J mol-1) revealed that adsorption efficiency increased with an increase in the process temperature. In fixed-bed column experiments, the effect of selected operating parameters such as bed depth, flow rate and initial dye concentration on the adsorption capacity was evaluated. Increase in bed height of adsorption columns leads to an extension of breakthrough point as well as the exhaustion time of adsorbent. However, the maximum adsorption capacities decrease with increases of flow rate. The breakthrough data fitted well to bed depth service time and Thomas models with high coefficient of determination, R 2 ≥ 94.

  1. Electron shuttle-mediated biotransformation of hexahydro-1,3,5-trinitro-1,3,5-triazine adsorbed to granular activated carbon.

    PubMed

    Millerick, Kayleigh; Drew, Scott R; Finneran, Kevin T

    2013-08-01

    Granular activated carbon (GAC) effectively removes hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) from groundwater but generates RDX-laden GAC that must be disposed of or regenerated. Batch reactors containing GAC to which RDX was preadsorbed were used in experiments to test the potential for adsorbed RDX reduction and daughter product formation using (i) chemically reduced anthrahydroquinone-2,6-disulfonate (AH2QDS), (ii) resting Geobacter metallireducens strain GS-15, and (iii) a combined system containing AQDS and GS-15. Approximately 97.0% of the adsorbed RDX was transformed in each of these experimental systems by 90 h. Chemically reduced AQDS (AH2QDS) transformed 99.2% of adsorbed RDX; formaldehyde was produced rapidly and was stoichiometric (3 mol HCHO per mol RDX). Geobacter metallireducens also reduced RDX with and without AQDS present. This is the first study to demonstrate biological transformation of RDX adsorbed to GAC. Formaldehyde increased and then decreased in biological systems, suggesting a previously unreported capacity for G. metallireducens to oxidize formaldehyde, which was confirmed with resting cell suspensions. These data suggest the masses of GAC waste currently produced by activated carbon at RDX remediation sites can be minimized, decreasing the carbon footprint of the treatment technology. Alternatively, this strategy may be used to develop a Bio-GAC system for ex situ RDX treatment. PMID:23837558

  2. Equilibrium adsorption isotherm studies of Cu (II) and Co (II) in high concentration aqueous solutions on Ag-TiO2-modified kaolinite ceramic adsorbents

    NASA Astrophysics Data System (ADS)

    Ajenifuja, E.; Ajao, J. A.; Ajayi, E. O. B.

    2016-03-01

    Photocatalytic ceramic adsorbents were prepared from locally sourced kaolinite clay minerals for the removal of copper and cobalt ions from high concentration aqueous solutions. The minerals were treated with mild acid before modification using silver nanoparticles sources and titanium-oxide nanoparticles. Batch adsorption experiment was carried out on the targeted ions and the results were analyzed by Langmuir and Freundlich equation at different concentrations (100-1000 mg/l). As-received raw materials do not exhibit any adsorption capacity. However, the adsorption isotherms for modified kaolinite clay ceramic adsorbents could be fitted well by the Langmuir model for Cu2+ and Co2+ with correlation coefficient (R) of up to 0.99705. The highest and lowest monolayer coverage (q max) were 93.023 and 30.497 mg/g for Cu2+ and Co2+, respectively. The separation factor (R L ) was less than one (<1), indicating that the adsorption of metal ions on modified ceramic adsorbent is favorable. The highest adsorbent adsorption capacity (K f ) and intensity (n) constants obtained from Freundlich model are 14.401 (Cu2+ on KLN-T) and 6.057 (Co2+ on KLN-T).

  3. Alkylammonium montmorillonites as adsorbents for organic vapors from air

    SciTech Connect

    Harper, M.; Purnell, C.J. )

    1990-01-01

    Montmorillonite clays may be modified by the exchange of the inorganic interlayer cations with alkylammonium ions, resulting in a fixed internal porosity. The pore size and shape depend on the nature of the alkylammonium ion. A number of different ions were used to prepare adsorbents with varying properties, and these were examined for their potential application to sampling organic vapors in air. Characterization involved determination of nitrogen and water contents, surface area, interlayer spacing, thermal stability, and breakthrough volumes of organic vapors. The adsorbent that showed the most promise (tetramethylammonium montmorillonite (TMA)) was further evaluated for use as an adsorbent in both thermal- and solvent-desorable sampling systems.

  4. The removal of chromium, nickel, and zinc from electroplating wastewater by adsorbing colloid flotation with a sodium dodecylsulfate/dodecanoic acid mixture

    SciTech Connect

    Sanciolo, P.; Harding, I.H.; Mainwaring, D.E. )

    1992-03-01

    The removal by adsorbing colloid flotation of Cr(III), Ni(II), and Zn(II) from chromium stream electroplating wastewater was investigated. Adsorbing colloid flotation involves the stripping of contaminants by adsorption or coprecipitation onto added colloidal material and its subsequent flotation by column flotation. The added colloid was prepared in situ by the hydrolysis of added metal (Fe(III))ions. Adsorbing colloid flotation using a single surfactant (SDS) in the batch mode was shown to result in poor results for real industrial samples, presumably due to the chemical complexity of such samples. However, a dual surfactant system (sodium dodecylsulfate (SDS) + dodecanoic acid (DA)) provided encouraging results. By using such a dual surfactant system, chromium stream electroplating wastewater was treated, successfully lowering metal ion contamination levels to below that required for discharge into typical metropolitan drainage systems. Flotation was found to be successful at near neutral pH conditions (7.5) and for several different (electroplating) industrial samples. Adsorbing colloid flotation in the continuous mode was investigated by using the dual surfactant system optimized in batch experiments. At flow rates encouraging to full-scale commercial applications, toxic metal ions (Cr(III), Ni(II), Zn(II)) were stripped from contaminated industrial samples to below the 100 ppm typically required for metropolitan discharge. A two-stage continuous processing scheme was investigated where once-treated effluent was passed through a second polishing column. Use of this two-stage process typically resulted in the stripping of toxic metal ions (from similar samples) to well below the 1 ppm level typically required for environmental discharge.

  5. Evaluation of Adsorption Properties for Cs and Sr Selective Adsorbents-13171

    SciTech Connect

    Nakai, Tomonori; Wakabayashi, Syunya; Mimura, Hitoshi; Niibori, Yuichi; Kurosaki, Fumio; Matsukura, Minoru; Tanigawa, Hiroshi; Ishizaki, Eiji

    2013-07-01

    The development of effective treatment and disposal methods is very urgent and important subject. Tohoku University and UNION SHOWA have developed various selective adsorbents (zeolites, zeolite sheets and composites loaded with insoluble ferrocyanides) for the effective decontamination of radioactive Cs{sup +} and Sr{sup 2+} As for Cs{sup +} adsorption, CST, chabazite and insoluble ferrocyanides composites had relatively large distribution coefficients (K{sub d}) above 10{sup 3} cm{sup 3}/g and excellent adsorption kinetics in seawater. Even after high temperature calcination at 1,100 deg. C, cesium was still immobilized in the calcined products of Cs{sup +}-zeolites, suggesting high immobilization ability of zeolites for Cs{sup +}. As for Sr{sup 2+} adsorption, A and X zeolites had relatively large K{sub d} values around 10{sup 2} cm{sup 3}/g, and zeolite sheet (A zeolite) exhibited excellent adsorption kinetics in seawater. Considering the decontamination of radioactive Sr{sup 2+} in groundwater, the effects of Ca{sup 2+} and Mg{sup 2+} ions on the K{sub d} value of Sr{sup 2+} were further examined by batch method. The K{sub d} value of Sr{sup 2+} was almost independent of Mg{sup 2+} concentration up to 2,500 ppm, while gradually lowered in the presence of Ca{sup 2+} above 200 ppm, due to the differences in the ionic radius of hydrated ion. The Cs{sup +} and Sr{sup 2+} adsorption ability for KNiFC-A (composite of A zeolite loaded with insoluble ferrocyanides) was examined by batch method. Here the matrix of composite (A zeolite) and loaded ferrocyanides (KNiFC) have high selectivity towards Sr{sup 2+} and Cs{sup +}, respectively. The K{sub d} values of Sr{sup 2+} and Cs{sup +} in seawater were estimated to be above 10{sup 2} and 10{sup 3} cm{sup 3}/g, respectively, indicating the effectiveness for the decontamination of both Sr{sup 2+} and Cs{sup +}. The basic data on the Cs{sup +} and Sr{sup 2+} adsorption properties for selective adsorbents are effective for

  6. 40 CFR 205.57-6 - Acceptance and rejection of batches.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 25 2014-07-01 2014-07-01 false Acceptance and rejection of batches... Acceptance and rejection of batches. (a) The batch from which a batch sample is selected will be accepted or... equal to the acceptance number or greater than or equal to the rejection number appropriate for...

  7. 40 CFR 205.57-6 - Acceptance and rejection of batches.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 26 2012-07-01 2011-07-01 true Acceptance and rejection of batches... Acceptance and rejection of batches. (a) The batch from which a batch sample is selected will be accepted or... equal to the acceptance number or greater than or equal to the rejection number appropriate for...

  8. 40 CFR 63.1327 - Batch process vents-reporting requirements.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 11 2010-07-01 2010-07-01 true Batch process vents-reporting... Batch process vents—reporting requirements. (a) The owner or operator of a batch process vent or... in § 63.1335(e)(5). (1) For each batch process vent complying § 63.1322(a) and each aggregate...

  9. 40 CFR 63.486 - Batch front-end process vent provisions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 9 2010-07-01 2010-07-01 false Batch front-end process vent provisions... Batch front-end process vent provisions. (a) Batch front-end process vents. Except as specified in paragraph (b) of this section, owners and operators of new and existing affected sources with batch...

  10. Novel Anionic Clay Adsorbents for Boiler-Blow Down Waters Reclaim and Reuse

    SciTech Connect

    Muhammad Sahimi; Theodore T. Tsotsis

    2005-12-01

    Our goal in this study is to utilize novel anionic clay sorbents for treating and reclaiming/reusing power-plant effluents, in particular, boiler blow-down waters containing heavy metals, such as As and Se. Developing and using novel materials for such application is dictated by the challenge posed by reclaiming and recycling these too-clean-to-clean effluent streams, generated during electricity production, whose contaminant levels are in the ppm/ppb (or even less) trace levels. During the study model blow-down streams have been treated in batch experiments. Adsorption isotherms as a function of pH/temperature have been established for both As and Se. Adsorption rates have also measured as a function of concentration, temperature, pH, and space time. For both the equilibrium and rate measurements, we have studied the As/Se interaction, and competition from background anions. A homogeneous surface diffusion model is used to describe the experimental kinetic data. The estimated diffusivity values are shown to depend on the particle size. On the other hand, a model taking into account the polycrystalline nature of these adsorbent particles, and the presence of an intercrystallite porous region predicts correctly that the surface diffusivity is particle size independent. A mathematical model to describe flow experiments in packed-beds has also been developed during phase I of this project. The goal is to validate this model with flow experiments in packed-beds during the phase II of this project, to determine the adsorption capacity under flow conditions, and to compare it with the capacity estimated from the adsorption isotherms determined from the batch studies.

  11. Material prepared from drinking waterworks sludge as adsorbent for ammonium removal from wastewater

    NASA Astrophysics Data System (ADS)

    Yang, Lan; Wei, Jie; Liu, Zhongyuan; Wang, Jianli; Wang, Dongtian

    2015-03-01

    Drinking waterworks sludge (DWS) is not an effective adsorbent for ammonium removal without any treatment. In this study, DWS was used as a starting material to prepare ammonium adsorbent (M-DWS) by means of an ultrasonic assisted extraction and synthesis method. Two materials (M-DWS1# and M-DWS2#) were prepared according to two different routes. The composition, structure, and surface properties of DWS and M-DWS were characterized and their ammonium adsorption abilities were examined. Characterization results showed that the lamellar structure of DWS was converted into the spherical units of M-DWS and that the cation exchange capacity and specific surface area of M-DWS were many times higher than that of DWS. Batch test results indicated that the adsorption equilibrium data of M-DWS fitted well to both the Langmuir and Frendlich isotherms. The maximum adsorption capacity of M-DWS1# and M-DWS2# evaluated from the Langmuir isotherm was 6.11 mg/g and 5.10 mg/g, respectively. It was also observed that the initial pH affected ammonium adsorption on M-DWS greatly. Under an optimum pH of 7-8, the highest ammonium removal rate of 90% for M-DWS1# and 80% for M-DWS2# were achieved at an initial concentration of 50 mg NH4+/L. The advantage of M-DWS2# lies in its higher yield and less waste discharge compared with M-DWS1#.

  12. Towards Batched Linear Solvers on Accelerated Hardware Platforms

    SciTech Connect

    Haidar, Azzam; Dong, Tingzing Tim; Tomov, Stanimire; Dongarra, Jack J

    2015-01-01

    As hardware evolves, an increasingly effective approach to develop energy efficient, high-performance solvers, is to design them to work on many small and independent problems. Indeed, many applications already need this functionality, especially for GPUs, which are known to be currently about four to five times more energy efficient than multicore CPUs for every floating-point operation. In this paper, we describe the development of the main one-sided factorizations: LU, QR, and Cholesky; that are needed for a set of small dense matrices to work in parallel. We refer to such algorithms as batched factorizations. Our approach is based on representing the algorithms as a sequence of batched BLAS routines for GPU-contained execution. Note that this is similar in functionality to the LAPACK and the hybrid MAGMA algorithms for large-matrix factorizations. But it is different from a straightforward approach, whereby each of GPU's symmetric multiprocessors factorizes a single problem at a time. We illustrate how our performance analysis together with the profiling and tracing tools guided the development of batched factorizations to achieve up to 2-fold speedup and 3-fold better energy efficiency compared to our highly optimized batched CPU implementations based on the MKL library on a two-sockets, Intel Sandy Bridge server. Compared to a batched LU factorization featured in the NVIDIA's CUBLAS library for GPUs, we achieves up to 2.5-fold speedup on the K40 GPU.

  13. Adsorption of Methyl Tertiary Butyl Ether on Granular Zeolites: Batch and Column Studies

    PubMed Central

    Abu-Lail, Laila; Bergendahl, John A.; Thompson, Robert W.

    2010-01-01

    Methyl tertiary butyl ether (MTBE) has been shown to be readily removed from water with powdered zeolites, but the passage of water through fixed beds of very small powdered zeolites produces high friction losses not encountered in flow through larger sized granular materials. In this study, equilibrium and kinetic adsorption of MTBE onto granular zeolites, a coconut shell granular activated carbon (CS-1240), and a commercial carbon adsorbent (CCA) sample was evaluated. In addition, the effect of natural organic matter (NOM) on MTBE adsorption was evaluated. Batch adsorption experiments determined that ZSM-5 was the most effective granular zeolite for MTBE adsorption. Further equilibrium and kinetic experiments verified that granular ZSM-5 is superior to CS-1240 and CCA in removing MTBE from water. No competitive-adsorption effects between NOM and MTBE were observed for adsorption to granular ZSM-5 or CS-1240, however there was competition between NOM and MTBE for adsorption onto the CCA granules. Fixed-bed adsorption experiments for longer run times were performed using granular ZSM-5. The bed depth service time model (BDST) was used to analyze the breakthrough data. PMID:20153106

  14. 40 CFR 63.463 - Batch vapor and in-line cleaning machine standards.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... carbon adsorber that meets the requirements of paragraph (e)(2)(vii) of this section. (b) Except as... device, carbon adsorber. 10 Freeboard ratio of 1.0, superheated vapor, carbon adsorber. Note: Unlike most of the control techniques available for complying with this rule, carbon adsorbers are not...

  15. 40 CFR 63.463 - Batch vapor and in-line cleaning machine standards.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... carbon adsorber that meets the requirements of paragraph (e)(2)(vii) of this section. (b) Except as... device, carbon adsorber. 10 Freeboard ratio of 1.0, superheated vapor, carbon adsorber. Note: Unlike most of the control techniques available for complying with this rule, carbon adsorbers are not...

  16. Radiation grafted adsorbents for newly emerging environmental applications

    NASA Astrophysics Data System (ADS)

    Mahmoud Nasef, Mohamed; Ting, T. M.; Abbasi, Ali; Layeghi-moghaddam, Alireza; Sara Alinezhad, S.; Hashim, Kamaruddin

    2016-01-01

    Radiation induced grafting (RIG) is acquired to prepare a number of adsorbents for newly emerging environmental applications using a single route involving RIG of glycidymethacrylate (GMA) onto polyethylene-polypropylene (PE-PP) non-woven fabric. The grafted fabric was subjected to one of three functionalization reactions to impart desired ionic characters. This included treatment with (1) N-dimethyl-D-glucamine, (2) triethylamine and (3) triethylamine and alkalisation with KOH. Fourier transform infrared spectroscopy (FTIR) and scanning electron microscope (SEM) were used to study the changes in chemical and physical structures of the obtained fibrous adsorbents. The potential applications of the three adsorbents for removal of boron from solutions, capturing CO2 from CO2/N2 mixtures and catalysing transesterification of triacetin/methanol to methyl acetate (biodiesel) were explored. The obtained fibrous adsorbents provide potential alternatives to granular resins for the investigated applications and require further development.

  17. SUPERCRITICAL FLUID EXTRACTION OF PARTICULATE AND ADSORBENT MATERIALS

    EPA Science Inventory

    The report is a summary of work performed by PNL on the extraction of semivolatile organic materials (SVOCs), for example, polynuclear aromatic compounds, from various adsorbents and environmental matrices, using supercritical fluids (SCFs) as extractants. The results of the work...

  18. Anomalous thermal denaturing of proteins adsorbed to nanoparticles

    NASA Astrophysics Data System (ADS)

    Teichroeb, J. H.; Forrest, J. A.; Ngai, V.; Jones, L. W.

    2006-09-01

    We have used localized surface plasmon resonance (LSPR) to monitor the structural changes that accompany thermal denaturing of bovine serum albumin (BSA) adsorbed onto gold nanospheres of size 5nm-60nm. The effect of the protein on the LSPR was monitored by visible extinction spectroscopy. The position of the resonance is affected by the conformation of the adsorbed protein layer, and as such can be used as a very sensitive probe of thermal denaturing that is specific to the adsorbed protein. The results are compared to detailed calculations and show that full calculations can lead to significant increases in knowledge where gold nanospheres are used as biosensors. Thermal denaturing on spheres with diameter > 20 nm show strong similarity to bulk calorimetric studies of BSA in solution. BSA adsorbed on nanospheres with d ⩽ 15nm shows a qualitative difference in behavior, suggesting a sensitivity of denaturing characteristics on local surface curvature. This may have important implications for other protein-nanoparticle interactions.

  19. Removal of adsorbed gases with CO2 snow

    NASA Astrophysics Data System (ADS)

    Zito, Richard R.

    1991-09-01

    During the outgassing of orbiting astronomical observatories, the condensation of molecular species on optical surfaces can create difficulties for astronomers. The problem is particularly severe in ultraviolet astronomy where the adsorption of only a few atomic layers of some substances can be very damaging. In this paper the removal of adsorbed atomic layers using carbon dioxide snow is discussed. The rate of removal of adsorbed layers of isopropyl alcohol, Freon TF, and deionized distilled water on Teflon substrates was experimentally determined. The removal of fingerprints (containing fatty acids such as stearic acid) from optical surfaces is also demonstrated. The presence and rate of removal of the multilayers was monitored by detecting the molecular dipole field of adsorbed molecular species. For isopropyl alcohol, Freon TF (trichlorotrifluoroethane), and water adsorbed multilayers were removed in under 1.5 seconds. Fingerprint removal was much more difficult and required 20 seconds of spraying with a mixture of carbon dioxide snow flakes and atomized microdroplets of isopropyl alcohol.

  20. Electronic structure of benzene adsorbed on Ni and Cu surfaces

    SciTech Connect

    Weinelt, M.; Nilsson, A.; Wassdahl, N.

    1997-04-01

    Benzene has for a long time served as a prototype adsorption system of large molecules. It adsorbs with the molecular plane parallel to the surface. The bonding of benzene to a transition metal is typically viewed to involve the {pi} system. Benzene adsorbs weakly on Cu and strongly on Ni. It is interesting to study how the adsorption strength is reflected in the electronic structure of the adsorbate-substrate complex. The authors have used X-ray Emission (XE) and X-ray Absorption (XA) spectroscopies to selectively study the electronic states localized on the adsorbed benzene molecule. Using XES the occupied states can be studies and with XAS the unoccupied states. The authors have used beamline 8.0 and the Swedish endstation equipped with a grazing incidence x-ray spectrometer and a partial yield absorption detector. The resolution in the XES and XAS were 0.5 eV and 0.05 eV, respectively.

  1. Trace contaminant studies of HSC adsorbent. M.S. Thesis

    NASA Technical Reports Server (NTRS)

    Yieh, D. T. N.

    1978-01-01

    The adsorption and desorption of fifteen trace contaminants on HSC (polyethylenimine coated acrylic ester) adsorbent were experimentally investigated with the following two objectives: to test the removal potential and the adsorption reversibility of the selected trace contaminants, and to test the effect a preadsorbed trace contaminant has on the CO2 adsorption capacity. The experimental method for acquiring the adsorption equilibrium data used is based on the volumetric (or displacement) concept of vacuum adsorption. From the experimental results, it was found that the HSC adsorbent has good adsorption potential for contaminants of alcohol compounds, esters, and benzene compounds; whereas, adsorption of ketone compounds, oxidizing and reducing agents are detrimental to the adsorbent. In addition, all liquid contaminants reduce the CO2 capacity of HSC adsorbent.

  2. New insights into perfluorinated adsorbents for analytical and bioanalytical applications.

    PubMed

    Marchetti, Nicola; Guzzinati, Roberta; Catani, Martina; Massi, Alessandro; Pasti, Luisa; Cavazzini, Alberto

    2015-01-01

    Perfluorinated (F-) adsorbents are generally prepared by bonding perfluoro-functionalized silanes to silica gels. They have been employed for a long time essentially as media for solid-phase extraction of F-molecules or F-tagged molecules in organic chemistry and heterogeneous catalysis. More recently, this approach has been extended to proteomics and metabolomics. Owing to their unique physicochemical properties, namely fluorophilicity and proteinophilicity, and a better understanding of some fundamental aspects of their behavior, new applications of F-adsorbents in the field of environmental science and bio-affinity studies can be envisaged. In this article, we revisit the most important features of F-adsorbents by focusing, in particular, on some basic information that has been recently obtained through (nonlinear) chromatographic studies. Finally, we try to envisage new applications and possibilities that F-adsorbents will allow in the near future. PMID:25358910

  3. Adsorption of β-galactosidase on silica and aluminosilicate adsorbents

    NASA Astrophysics Data System (ADS)

    Atyaksheva, L. F.; Dobryakova, I. V.; Pilipenko, O. S.

    2015-03-01

    It is shown that adsorption of β-galactosidase of Aspergillus oryzae fungi on mesoporous and biporous silica and aluminosilicate adsorbents and the rate of the process grow along with the diameter of the pores of the adsorbent. It is found that the shape of the adsorption isotherms changes as well, depending on the texture of the adsorbent: the Michaelis constant rises from 0.3 mM for the enzyme in solution to 0.4-0.5 mM for the enzyme on a surface in the hydrolysis of o-nitrophenyl-β-D-galactopyranoside. It is concluded that β-galactosidase displays its maximum activity on the surface of biporous adsorbents.

  4. Oil palm biomass as an adsorbent for heavy metals.

    PubMed

    Vakili, Mohammadtaghi; Rafatullah, Mohd; Ibrahim, Mahamad Hakimi; Abdullah, Ahmad Zuhairi; Salamatinia, Babak; Gholami, Zahra

    2014-01-01

    Many industries discharge untreated wastewater into the environment. Heavy metals from many industrial processes end up as hazardous pollutants of wastewaters.Heavy metal pollution has increased in recent decades and there is a growing concern for the public health risk they may pose. To remove heavy metal ions from polluted waste streams, adsorption processes are among the most common and effective treatment methods. The adsorbents that are used to remove heavy metal ions from aqueous media have both advantages and disadvantages. Cost and effectiveness are two of the most prominent criteria for choosing adsorbents. Because cost is so important, great effort has been extended to study and find effective lower cost adsorbents.One class of adsorbents that is gaining considerable attention is agricultural wastes. Among many alternatives, palm oil biomasses have shown promise as effective adsorbents for removing heavy metals from wastewater. The palm oil industry has rapidly expanded in recent years, and a large amount of palm oil biomass is available. This biomass is a low-cost agricultural waste that exhibits, either in its raw form or after being processed, the potential for eliminating heavy metal ions from wastewater. In this article, we provide background information on oil palm biomass and describe studies that indicate its potential as an alternative adsorbent for removing heavy metal ions from wastewater. From having reviewed the cogent literature on this topic we are encouraged that low-cost oil-palm-related adsorbents have already demonstrated outstanding removal capabilities for various pollutants.Because cost is so important to those who choose to clean waste streams by using adsorbents, the use of cheap sources of unconventional adsorbents is increasingly being investigated. An adsorbent is considered to be inexpensive when it is readily available, is environmentally friendly, is cost-effective and be effectively used in economical processes. The

  5. Residence time determination for adsorbent beds of different configurations

    SciTech Connect

    Otermat, J.E.; Wikoff, W.O.; Kovach, J.L.

    1995-02-01

    The residence time calculations of ASME AG-1 Code, Section FC, currently specify a screen surface area method, that is technically incorrect. Test data has been obtained on Type II adsorber trays of different configurations to establish residence time in the adsorber trays. These data indicate that the air volume/carbon volume ratio or the average screen area are more appropriate for the calculation of the residence time calculation than the currently used, smallest screen area basis.

  6. Radiation synthesis of spherical cellulose-based adsorbent for efficient adsorption and detoxification of Cr(VI)

    NASA Astrophysics Data System (ADS)

    Dong, Zhen; Zhao, Jing; Du, Jifu; Li, Cancan; Zhao, Long

    2016-09-01

    Spherical cellulose-based adsorbent (2-AMPR) with 2-aminomethyl pyridine was synthesized by radiation method. The adsorption behaviors of 2-AMPR for Cr(VI) removal were evaluated through batch and column experiments. The results presented that the adsorption kinetics well obeyed pseudo-second-order mode and the adsorption isotherm of Cr(VI) followed the Langmuir model with adsorption capacity of 209.6 mg/g at optimal pH 2.0. Dynamical experiments revealed that the 2-AMPR could selectively and simultaneously separate and detoxify trace amount of Cr(VI) even from simulated electroplating wastewater including high concentration of Cu(II), Ni(II) and Zn(II) ions. Additionally, FTIR and XPS analysis verified that part of Cr(VI) was reduced to Cr(III) during adsorption process by adsorption-reduction mechanism.

  7. Bionanocomposites based on layered silicates and cationic starch as eco-friendly adsorbents for hexavalent chromium removal.

    PubMed

    Koriche, Yamina; Darder, Margarita; Aranda, Pilar; Semsari, Saida; Ruiz-Hitzky, Eduardo

    2014-07-21

    Functional bionanocomposites based on two layered silicates, the commercial montmorillonite known as Cloisite®Na and a natural bentonite from Algeria, were prepared by intercalation of cationic starch, synthesized with two different degrees of substitution, 0.85 and 0.55. After characterization of the prepared bionanocomposites by XRD and zeta potential measurements, batch studies were conducted to evaluate the adsorption capacity of hexavalent chromium anions from aqueous solution. The adsorption isotherms, adsorption kinetics, and the effect of pH on the process were studied. The removal efficiency was evaluated in the presence of competing anions such as NO3(-), ClO4(-), SO4(2-) and Cl(-). In order to regenerate the adsorbent for its repeated use, the regeneration process was studied in two different extractant solutions, 0.1 M NaCl at pH 10 and 0.28 M Na2CO3 at pH 12. PMID:24658793

  8. Application of gain scheduling to the control of batch bioreactors

    NASA Technical Reports Server (NTRS)

    Cardello, Ralph; San, Ka-Yiu

    1987-01-01

    The implementation of control algorithms to batch bioreactors is often complicated by the inherent variations in process dynamics during the course of fermentation. Such a wide operating range may render the performance of fixed gain PID controllers unsatisfactory. In this work, a detailed study on the control of batch fermentation is performed. Furthermore, a simple batch controller design is proposed which incorporates the concept of gain-scheduling, a subclass of adaptive control, with oxygen uptake rate as an auxiliary variable. The control of oxygen tension in the biorector is used as a vehicle to convey the proposed idea, analysis and results. Simulation experiments indicate significant improvement in controller performance can be achieved by the proposed approach even in the presence of measurement noise.

  9. Efforts to Consolidate Chalcogels with Adsorbed Iodine

    SciTech Connect

    Riley, Brian J.; Pierce, David A.; Chun, Jaehun

    2013-08-28

    This document discusses ongoing work with non-oxide aerogels, called chalcogels, that are under development at the Pacific Northwest National Laboratory as sorbents for gaseous iodine. Work was conducted in fiscal year 2012 to demonstrate the feasibility of converting Sn2S3 chalcogel without iodine into a glass. This current document summarizes the work conducted in fiscal year 2013 to assess the consolidation potential of non-oxide aerogels with adsorbed iodine. The Sn2S3 and Sb13.5Sn5S20 chalcogels were selected for study. The first step in the process for these experiments was to load them with iodine (I2). The I2 uptake was ~68 mass% for Sn2S3 and ~50 mass% for Sb13.5Sn5S20 chalcogels. X-ray diffraction (XRD) of both sets of sorbents showed that metal-iodide complexes were formed during adsorption, i.e., SnI4 for Sn2S3 and SbI3 for Sb13.5Sn5S20. Additionally, metal-sulfide-iodide complexes were formed, i.e., SnSI for Sn2S3 and SbSI for Sb13.5Sn5S20. No XRD evidence for unreacted iodine was found in any of these samples. Once the chalcogels had reached maximum adsorption, the consolidation potential was assessed. Here, the sorbents were heated for consolidation in vacuum-sealed quartz vessels. The Sb13.5Sn5S20 chalcogel was heated both (1) in a glassy carbon crucible within a fused quartz tube and (2) in a single-containment fused quartz tube. The Sn2S3 chalcogel was only heated in a single-containment fused quartz tube. In both cases with the single-containment fused quartz experiments, the material consolidated nicely. However, in both cases, there were small fractions of metal iodides not incorporated into the final product as well as fused quartz particles within the melt due to the sample attacking the quartz wall during the heat treatment. The Sb13.5Sn5S20 did not appear to attack the glassy carbon crucible so, for future experiments, it would be ideal to apply a coating, such as pyrolytic graphite, to the inner walls of the fused quartz vessel to prevent

  10. Application of Silver Impregnated Iodine Adsorbent to Nuclear Facilities

    NASA Astrophysics Data System (ADS)

    Fukasawa, Tetsuo; Nakamura, Tomotaka; Kondo, Yoshikazu; Funabashi, Kiyomi

    Radioactive iodine is one of the most important nuclides to be prevented for release from nuclear facilities and many facilities have off-gas treatment systems to minimize the volatile nuclides dispersion to the environment. Silver impregnated inorganic adsorbents were known as inflammable and stable fixing materials for iodine and the authors started to develop 25 years ago a kind of inorganic adsorbent that has better capability compared with conventional ones. Aluminum oxide (Alumina) was selected as a carrier material and silver nitrate as an impregnated one. Pore diameters were optimized to avoid the influence of impurities such as humidity in the off-gas stream at lower temperatures. Experiments and improvements were alternately conducted for the new adsorbent. The tests were carried out in various conditions to confirm the performance of the developed adsorbent, which clarified its good ability to remove iodine. Silver nitrate impregnated alumina adsorbent (AgA) has about twice the capacity for iodine adsorption and higher iodine removal efficiency at relatively high humidity than conventional ones. The AgA chemically and stably fixes radioactive iodine and fits the storage and disposal of used adsorbent. AgA is now and will be applied to nuclear power plants, reprocessing plants, and research facilities.

  11. Cryogenic adsorber design in a helium refrigeration system

    NASA Astrophysics Data System (ADS)

    Hu, Zhongjun; Zhang, Ning; Li, Zhengyu; Li, Q.

    2012-06-01

    The cryogenic adsorber is specially designed to eliminate impurities in gaseous helium such as O2, and N2 which is normally difficult to remove, based on the reversible cryotrapping of impurities on an activated carbon bed. The coconut shell activated carbon is adopted because of its developed micropore structure and specific surface area. This activated carbon adsorption is mostly determined by the micropore structure, and the adsorption rate of impurities is inversely proportional to the square of the particle sizes. The active carbon absorber's maximum permissible flow velocity is 0.25 m/s. When the gas flow velocity increases, the adsorption diffusion rate of the adsorbent is reduced, because an increase in the magnitude of the velocity resulted in a reduced amount of heat transfer to a unit volume of impure gas. According to the numerical simulation of N2 adsorption dynamics, the appropriate void tower link speed and the saturated adsorption capacity are determined. Then the diameter and height of the adsorber are designed. The mass transfer length should be taken into account in the adsorber height design. The pressure decrease is also calculated. The important factors that influence the adsorber pressure decrease are the void tower speed, the adsorbed layer height, and the active carbon particle shape and size.

  12. Control of acid gases using a fluidized bed adsorber.

    PubMed

    Chiang, Bo-Chin; Wey, Ming-Yen; Yeh, Chia-Lin

    2003-08-01

    During incineration, secondary pollutants such as acid gases, organic compounds, heavy metals and particulates are generated. Among these pollutants, the acid gases, including sulfur oxides (SO(x)) and hydrogen chloride (HCl), can cause corrosion of the incinerator piping and can generate acid rain after being emitted to the atmosphere. To address this problem, the present study used a novel combination of air pollution control devices (APCDs), composed of a fluidized bed adsorber integrated with a fabric filter. The major objective of the work is to demonstrate the performance of a fluidized bed adsorber for removal of acid gases from flue gas of an incinerator. The adsorbents added in the fluidized bed adsorber were mainly granular activated carbon (AC; with or without chemical treatment) and with calcium oxide used as an additive. The advantages of a fluidized bed reactor for high mass transfer and high gas-solid contact can enhance the removal of acid gases when using a dry method. On the other hand, because the fluidized bed can filter particles, fine particles prior to and after passing through the fluidized bed adsorber were investigated. The competing adsorption on activated carbon between different characteristics of pollutants was also given preliminary discussion. The results indicate that the removal efficiencies of the investigated acid gases, SO(2) and HCl, are higher than 94 and 87%, respectively. Thus, a fluidized bed adsorber integrated with a fabric filter has the potential to replace conventional APCDs, even when there are other pollutants at the same time. PMID:12935758

  13. A High-Fidelity Batch Simulation Environment for Integrated Batch and Piloted Air Combat Simulation Analysis

    NASA Technical Reports Server (NTRS)

    Goodrich, Kenneth H.; McManus, John W.; Chappell, Alan R.

    1992-01-01

    A batch air combat simulation environment known as the Tactical Maneuvering Simulator (TMS) is presented. The TMS serves as a tool for developing and evaluating tactical maneuvering logics. The environment can also be used to evaluate the tactical implications of perturbations to aircraft performance or supporting systems. The TMS is capable of simulating air combat between any number of engagement participants, with practical limits imposed by computer memory and processing power. Aircraft are modeled using equations of motion, control laws, aerodynamics and propulsive characteristics equivalent to those used in high-fidelity piloted simulation. Databases representative of a modern high-performance aircraft with and without thrust-vectoring capability are included. To simplify the task of developing and implementing maneuvering logics in the TMS, an outer-loop control system known as the Tactical Autopilot (TA) is implemented in the aircraft simulation model. The TA converts guidance commands issued by computerized maneuvering logics in the form of desired angle-of-attack and wind axis-bank angle into inputs to the inner-loop control augmentation system of the aircraft. This report describes the capabilities and operation of the TMS.

  14. 40 CFR Table 7 to Subpart Jjj of... - Group 1 Batch Process Vents and Aggregate Batch Vent Streams-Monitoring, Recordkeeping, and...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Aggregate Batch Vent Streams-Monitoring, Recordkeeping, and Reporting Requirements 7 Table 7 to Subpart JJJ... Standards for Hazardous Air Pollutant Emissions: Group IV Polymers and Resins Pt. 63, Subpt. JJJ, Table 7 Table 7 to Subpart JJJ of Part 63—Group 1 Batch Process Vents and Aggregate Batch Vent...

  15. 40 CFR Table 7 to Subpart Jjj of... - Group 1 Batch Process Vents and Aggregate Batch Vent Streams-Monitoring, Recordkeeping, and...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Aggregate Batch Vent Streams-Monitoring, Recordkeeping, and Reporting Requirements 7 Table 7 to Subpart JJJ..., Subpt. JJJ, Table 7 Table 7 to Subpart JJJ of Part 63—Group 1 Batch Process Vents and Aggregate Batch... presented in this table) Concentration level or reading indicated by an organic monitoring device at...

  16. 40 CFR Table 7 to Subpart Jjj of... - Group 1 Batch Process Vents and Aggregate Batch Vent Streams-Monitoring, Recordkeeping, and...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Aggregate Batch Vent Streams-Monitoring, Recordkeeping, and Reporting Requirements 7 Table 7 to Subpart JJJ..., Subpt. JJJ, Table 7 Table 7 to Subpart JJJ of Part 63—Group 1 Batch Process Vents and Aggregate Batch... presented in this table) Concentration level or reading indicated by an organic monitoring device at...

  17. 40 CFR Table 7 to Subpart Jjj of... - Group 1 Batch Process Vents and Aggregate Batch Vent Streams-Monitoring, Recordkeeping, and...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Aggregate Batch Vent Streams-Monitoring, Recordkeeping, and Reporting Requirements 7 Table 7 to Subpart JJJ... Standards for Hazardous Air Pollutant Emissions: Group IV Polymers and Resins Pt. 63, Subpt. JJJ, Table 7 Table 7 to Subpart JJJ of Part 63—Group 1 Batch Process Vents and Aggregate Batch Vent...

  18. Batch-related sterile endophthalmitis following intravitreal injection of bevacizumab

    PubMed Central

    Entezari, Morteza; Ramezani, Alireza; Ahmadieh, Hamid; Ghasemi, Hassan

    2014-01-01

    Background: To report a series of patients with sterile endophthalmitis after intravitreal bevacizumab (IVB) injection from 2 different batches of bevacizumab. Materials and Methods: Records of 11 eyes with severe inflammation after IVB injections from two different batches (7 eyes from one and 4 from the other) on two separate days were evaluated. Fifteen eyes of 15 patients in one day were treated with one batch and 18 eyes of 17 patients were treated another day using another batch injected for different retinal diseases. Each batch was opened on the day of injection. We used commercially available bevacizumab (100 mg/4 ml) kept at 4°C. Severe cases with hypopyon were admitted to the ward and underwent anterior chamber and vitreous tap for direct smear and culture. Results: Pain, redness and decreased vision began after 11-17 days. All had anterior chamber and vitreous reactions and 5 had hypopyon. Antibiotics and corticosteroids were initiated immediately, but the antibiotics were discontinued after negative culture results. Visual acuity returned to pre-injection levels in 10 eyes after 1 month and only in one eye pars plana vitrectomy was performed. Mean VA at the time of presentation with inflammation (1.76 ± 0.78 logMAR) decreased significantly (P =0.008) compared to the initial mean corrected VA (1.18 ± 0.55 logMAR); however, final mean corrected VA (1.02 ± 0.48 logMAR) improved in comparison with the baseline but not to a significant level (P =0.159). Conclusions: We report a cluster of sterile endophthalmitis following intravitreal injection of bevacizumab from the same batch of bevacizumab that has a favorable prognosis. PMID:23619494

  19. Use of residues and by-products of the olive-oil production chain for the removal of pollutants from environmental media: A review of batch biosorption approaches.

    PubMed

    Anastopoulos, Ioannis; Massas, Ioannis; Ehaliotis, Constantinos

    2015-01-01

    Residues and by-products of the olive-oil production chain have been widely studied as biosorbents for the removal of various pollutants from environmental media due to their significant adsorption properties, low cost, production at local level and renewability. In this review, adsorbents developed from olive-tree cultivation residues and olive-oil extraction by-products and wastes are examined, and their sorption characteristics are described and discussed. Recent information obtained using batch sorption studies is summarized and the adsorption mechanisms involved, regarding various aquatic and soil pollutants (metal ions, dyes, radionuclides, phenolic compounds, pesticides) are presented and discussed. It is evident that several biosorbents show the potential to effectively remove a wide variety of pollutants from aqueous solutions, especially Pb and Cd. However, there is need to (a) develop standardized batch study protocols, and potentially reference materials, for effective cross-evaluation of biosorbents of similar nature and for improved understanding of mechanisms involved and (b) investigate scaling-up and regeneration issues that hold back industry-level application of preselected adsorbents. PMID:25901848

  20. Biodegradation of high explosives on granular activated carbon [GAC]: Enhanced desorption of high explosives from GAC -- Batch studies

    SciTech Connect

    Morley, M.C.; Speitel, G.E. Jr.

    1999-03-01

    Adsorption to GAC is an effective method for removing high explosives (HE) compounds from water, but no permanent treatment is achieved. Bioregeneration, which treats adsorbed contaminants by desorption and biodegradation, is being developed as a method for reducing GAC usage rates and permanently degrading RDX and HMX. Because desorption is often the limiting mass transfer mechanism in bioregeneration systems, several methods for increasing the rate and extent of desorption of RDX and HMX are being studied. These include use of cosolvents (methanol and ethanol), surfactants (both anionic and nonionic), and {beta}- and {gamma}-cyclodextrins. Batch experiments to characterize the desorption of these HEs from GAC have been completed using Northwestern LB-830, the GAC being used at Pantex. Over a total of 11 days of desorption, about 3% of the adsorbed RDX was desorbed from the GAC using buffered water as the desorption fluid. In comparison, about 96% of the RDX was extracted from the GAC by acetonitrile over the same desorption period. Ethanol and methanol were both effective in desorbing RDX and HMX; higher alcohol concentrations were able to desorb more HE from the GAC. Surfactants varied widely in their abilities to enhance desorption of HEs. The most effective surfactant that was studied was sodium dodecyl sulfate (SDS), which desorbed 56.4% of the adsorbed RDX at a concentration of 500 mg SDS/L. The cyclodextrins that were used were marginally more effective than water. Continuous-flow column tests are underway for further testing the most promising of these methods. These results will be compared to column experiments that have been completed under baseline conditions (using buffered water as the desorption fluid). Results of this research will support modeling and design of further desorption and bioregeneration experiments.

  1. Gold recovery from low concentrations using nanoporous silica adsorbent

    NASA Astrophysics Data System (ADS)

    Aledresse, Adil

    The development of high capacity adsorbents with uniform porosity denoted 5%MP-HMS (5% Mercaptopropyl-Hexagonal Mesoporous Structure) to extract gold from noncyanide solutions is presented. The preliminary studies from laboratory simulated noncyanide gold solutions show that the adsorption capacities of these materials are among the highest reported. The high adsorption saturation level of these materials, up to 1.9 mmol/g (37% of the adsorbent weight) from gold chloride solutions (potassium tetrachloroaurate) and 2.9 mmol/g (57% of the adsorbent weight) from gold bromide solutions (potassium tetrabromoaurate) at pH = 2, is a noteworthy feature of these materials. This gold loading from [AuC4]- and [AuBr4 ]- solutions corresponds to a relative Au:S molar ratio of 2.5:1 and 3.8:1, respectively. These rates are significantly higher than the usual 1:1 (Au:S) ratio expected for metal ion binding with the material. The additional gold ions loaded have been spontaneously reduced to metallic gold in the mesoporous material. Experimental studies indicated high maximum adsorptions of gold as high as 99.9% recovery. Another promising attribute of these materials is their favourable adsorption kinetics. The MP-HMS reaches equilibrium (saturation) in less than 1 minute of exposure in gold bromide and less than 10 minutes in gold chloride. The MP-HMS materials adsorption is significantly improved by agitation and the adsorption capacity of Au (III) ions increases with the decrease in pH. The recovery of adsorbed gold and the regeneration of spent adsorbent were investigated for MP-HMS adsorbent. The regenerated adsorbent (MP-HMS) maintained its adsorption capacity even after repeated use and all the gold was successfully recovered from the spent adsorbent. For the fist time, a promising adsorbent system has been found that is capable of effectively concentrating gold thiosulphate complexes, whereas conventional carbon-inpulp (CIP) and carbon-in-leach (CIL) systems fail. The

  2. Dissolution retardation of solid silica during glass batch-melting

    SciTech Connect

    Hrma, Pavel R.; Marcial, Jose

    2011-07-15

    During glass-batch melting, solid silica (quartz) usually dissolves last. A retardation function was defined as a measure of the progressive inhibition of silica dissolution that occurs during batch melting. This function is based on the comparison of the measured rate of dissolution of silica particles with the hypothetical diffusion-controlled volume flux from regularly distributed particles with uniform concentration layers around them. The severe inhibition of silica dissolution has been attributed to the irregular spatial distribution of silica particles that is associated with the formation of nearly saturated melt at a portion of their surfaces. Irregular shapes and unequal sizes of particles also contribute to their extended lifetime.

  3. Stochastic growth logistic model with aftereffect for batch fermentation process

    NASA Astrophysics Data System (ADS)

    Rosli, Norhayati; Ayoubi, Tawfiqullah; Bahar, Arifah; Rahman, Haliza Abdul; Salleh, Madihah Md

    2014-06-01

    In this paper, the stochastic growth logistic model with aftereffect for the cell growth of C. acetobutylicum P262 and Luedeking-Piret equations for solvent production in batch fermentation system is introduced. The parameters values of the mathematical models are estimated via Levenberg-Marquardt optimization method of non-linear least squares. We apply Milstein scheme for solving the stochastic models numerically. The effciency of mathematical models is measured by comparing the simulated result and the experimental data of the microbial growth and solvent production in batch system. Low values of Root Mean-Square Error (RMSE) of stochastic models with aftereffect indicate good fits.

  4. Stochastic growth logistic model with aftereffect for batch fermentation process

    SciTech Connect

    Rosli, Norhayati; Ayoubi, Tawfiqullah; Bahar, Arifah; Rahman, Haliza Abdul; Salleh, Madihah Md

    2014-06-19

    In this paper, the stochastic growth logistic model with aftereffect for the cell growth of C. acetobutylicum P262 and Luedeking-Piret equations for solvent production in batch fermentation system is introduced. The parameters values of the mathematical models are estimated via Levenberg-Marquardt optimization method of non-linear least squares. We apply Milstein scheme for solving the stochastic models numerically. The effciency of mathematical models is measured by comparing the simulated result and the experimental data of the microbial growth and solvent production in batch system. Low values of Root Mean-Square Error (RMSE) of stochastic models with aftereffect indicate good fits.

  5. [Hydroxycinnamic acid levels of various batches from mugwort flowering tops].

    PubMed

    Fraisse, D; Carnat, A; Carnat, A-P; Guédon, D; Lamaison, J-L

    2003-07-01

    Dried flowering tops of 24 harvested batches (Artemisia vulgaris: 13; Artemisia verlotiorum: 11) and 12 batches of mugwort from commercial origin were examined. The levels of principal compounds averaged respectively: total hydroxycinnamic acids 6.09; 10.29 and 9.13%, chlorogenic acid 0.79; 2.05 and 1.35%, 1,5-dicaffeoylquinic acid 0.51; 4.01 and 1.25%, 3,5-dicaffeoylquinic acid 2.21; 1.25 and 2.60%. Specifications were discussed for an European Pharmacopoeial monography. PMID:12843960

  6. Evaluation of Sludge Batch 5 Qualification with ISDP Salt Batch 1 Compliance to DWPF Waste Acceptance Criteria

    SciTech Connect

    Shafer, A.

    2010-05-05

    The purpose of this report is to document the acceptability of Sludge Batch 5 with the initial macrobatch operation of the Interim Salt Disposition Project (ISDP) waste to the Defense Waste Processing Facility (DWPF). This report was prepared to comply with the requirements listed in the Waste Acceptance Criteria for Sludge, Actinide Removal Process (ARP), and Modular Caustic Side Solvent Extraction Unit (MCU) Process Transfers to 512-S and DWPF. The requirements for transfers to 512-S were evaluated during ISDP Salt Batch 1 qualification. The calculations of sludge concentrations are based entirely on the Tank 51 sample processed at SRNL. This is conservative because Tank 51 is blended with the dilute feed in the DWPF Feed Tank (Tank 40). This report documents the acceptability of sludge only as well as Sludge Batch 5 sludge slurry combined with ARP/MCU products for feed to DWPF. All criteria were met for unblended Tank 51 material.

  7. Fabricating electrospun cellulose nanofibre adsorbents for ion-exchange chromatography

    PubMed Central

    Dods, Stewart R.; Hardick, Oliver; Stevens, Bob; Bracewell, Daniel G.

    2015-01-01

    Protein separation is an integral step in biopharmaceutical manufacture with diffusion-limited packed bed chromatography remaining the default choice for industry. Rapid bind-elute separation using convective mass transfer media offers advantages in productivity by operating at high flowrates. Electrospun nanofibre adsorbents are a non-woven fibre matrix of high surface area and porosity previously investigated as a bioseparation medium. The effects of compression and bed layers, and subsequent heat treatment after electrospinning cellulose acetate nanofibres were investigated using diethylaminoethyl (DEAE) or carboxylate (COO) functionalisations. Transbed pressures were measured and compared by compression load, COO adsorbents were 30%, 70% and 90% higher than DEAE for compressions 1, 5 and 10 MPa, respectively, which was attributed to the swelling effect of hydrophilic COO groups. Dynamic binding capacities (DBCs) at 10% breakthrough were measured between 2000 and 12,000 CV/h (2 s and 0.3 s residence times) under normal binding conditions, and DBCs increased with reactant concentration from 4 to 12 mg BSA/mL for DEAE and from 10 to 21 mg lysozyme/mL for COO adsorbents. Comparing capacities of compression loads applied after electrospinning showed that the lowest load tested, 1 MPa, yielded the highest DBCs for DEAE and COO adsorbents at 20 mg BSA/mL and 27 mg lysozyme/mL, respectively. At 1 MPa, DBCs were the highest for the lowest flowrate tested but stabilised for flowrates above 2000 CV/h. For compression loads of 5 MPa and 10 MPa, adsorbents recorded lower DBCs than 1 MPa as a result of nanofibre packing and reduced surface area. Increasing the number of bed layers from 4 to 12 showed decreasing DBCs for both adsorbents. Tensile strengths were recorded to indicate the mechanical robustness of the adsorbent and be related to packing the nanofibre adsorbents in large scale configurations such as pleated cartridges. Compared with an

  8. Elution by Le Chatelier's principle for maximum recyclability of adsorbents: applied to polyacrylamidoxime adsorbents for extraction of uranium from seawater.

    PubMed

    Oyola, Yatsandra; Vukovic, Sinisa; Dai, Sheng

    2016-05-28

    Amidoxime-based polymer adsorbents have attracted interest within the last decade due to their high adsorption capacities for uranium and other rare earth metals from seawater. The ocean contains an approximated 4-5 billion tons of uranium and even though amidoxime-based adsorbents have demonstrated the highest uranium adsorption capacities to date, they are still economically impractical because of their limited recyclability. Typically, the adsorbed metals are eluted with a dilute acid solution that not only damages the amidoxime groups (metal adsorption sites), but is also not strong enough to remove the strongly bound vanadium, which decreases the adsorption capacity with each cycle. We resolved this challenge by incorporating Le Chatelier's principle to recycle adsorbents indefinitely. We used a solution with a high concentration of amidoxime-like chelating agents, such as hydroxylamine, to desorb nearly a 100% of adsorbed metals, including vanadium, without damaging the metal adsorption sites and preserving the high adsorption capacity. The method takes advantage of knowing the binding mode between the amidoxime ligand and the metal and mimics it with chelating agents that then in a Le Chatelier's manner removes metals by shifting to a new chemical equilibrium. For this reason the method is applicable to any ligand-metal adsorbent and it will make an impact on other extraction technologies. PMID:27117598

  9. Batch culture and repeated-batch culture of Cunninghamella bainieri 2A1 for lipid production as a comparative study

    PubMed Central

    Dashti, Marjan Ganjali; Abdeshahian, Peyman

    2015-01-01

    This research was performed based on a comparative study on fungal lipid production by a locally isolated strain Cunninghamella bainieri 2A1 in batch culture and repeated-batch culture using a nitrogen-limited medium. Lipid production in the batch culture was conducted to study the effect of different agitation rates on the simultaneous consumption of ammonium tartrate and glucose sources. Lipid production in the repeated-batch culture was studied by considering the effect of harvesting time and harvesting volume of the culture broth on the lipid accumulation. The batch cultivation was carried out in a 500 ml Erlenmeyer flask containing 200 ml of the fresh nitrogen-limited medium. Microbial culture was incubated at 30 °C under different agitation rates of 120, 180 and 250 rpm for 120 h. The repeated-batch culture was performed at three harvesting times of 12, 24 and 48 h using four harvesting cultures of 60%, 70%, 80% and 90%. Experimental results revealed that nitrogen source (ammonium tartrate) was fully utilized by C. bainieri 2A1 within 24 h in all agitation rates tested. It was also observed that a high amount of glucose in culture medium was consumed by C. bainieri 2A1 at 250 rpm agitation speed during the batch fermentation. Similar results showed that the highest lipid concentration of 2.96 g/L was obtained at an agitation rate of 250 rpm at 120 h cultivation time with the maximum lipid productivity of 7.0 × 10−2 mg/ml/h. On the other hand, experimental results showed that the highest lipid concentration produced in the repeated-batch culture was 3.30 g/L at the first cycle of 48 h harvesting time using 70% harvesting volume, while 0.23 g/L gamma-linolenic acid (GLA) was produced at the last cycle of 48 h harvesting time using 80% harvesting volume. PMID:26980997

  10. Batch culture and repeated-batch culture of Cunninghamella bainieri 2A1 for lipid production as a comparative study.

    PubMed

    Dashti, Marjan Ganjali; Abdeshahian, Peyman

    2016-03-01

    This research was performed based on a comparative study on fungal lipid production by a locally isolated strain Cunninghamella bainieri 2A1 in batch culture and repeated-batch culture using a nitrogen-limited medium. Lipid production in the batch culture was conducted to study the effect of different agitation rates on the simultaneous consumption of ammonium tartrate and glucose sources. Lipid production in the repeated-batch culture was studied by considering the effect of harvesting time and harvesting volume of the culture broth on the lipid accumulation. The batch cultivation was carried out in a 500 ml Erlenmeyer flask containing 200 ml of the fresh nitrogen-limited medium. Microbial culture was incubated at 30 °C under different agitation rates of 120, 180 and 250 rpm for 120 h. The repeated-batch culture was performed at three harvesting times of 12, 24 and 48 h using four harvesting cultures of 60%, 70%, 80% and 90%. Experimental results revealed that nitrogen source (ammonium tartrate) was fully utilized by C. bainieri 2A1 within 24 h in all agitation rates tested. It was also observed that a high amount of glucose in culture medium was consumed by C. bainieri 2A1 at 250 rpm agitation speed during the batch fermentation. Similar results showed that the highest lipid concentration of 2.96 g/L was obtained at an agitation rate of 250 rpm at 120 h cultivation time with the maximum lipid productivity of 7.0 × 10(-2) mg/ml/h. On the other hand, experimental results showed that the highest lipid concentration produced in the repeated-batch culture was 3.30 g/L at the first cycle of 48 h harvesting time using 70% harvesting volume, while 0.23 g/L gamma-linolenic acid (GLA) was produced at the last cycle of 48 h harvesting time using 80% harvesting volume. PMID:26980997

  11. Lipid production in batch and fed-batch cultures of Rhodosporidium toruloides from 5 and 6 carbon carbohydrates

    PubMed Central

    2012-01-01

    Background Microbial lipids are a potential source of bio- or renewable diesel and the red yeast Rhodosporidium toruloides is interesting not only because it can accumulate over 50% of its dry biomass as lipid, but also because it utilises both five and six carbon carbohydrates, which are present in plant biomass hydrolysates. Methods R. toruloides was grown in batch and fed-batch cultures in 0.5 L bioreactors at pH 4 in chemically defined, nitrogen restricted (C/N 40 to 100) media containing glucose, xylose, arabinose, or all three carbohydrates as carbon source. Lipid was extracted from the biomass using chloroform-methanol, measured gravimetrically and analysed by GC. Results Lipid production was most efficient with glucose (up to 25 g lipid L−1, 48 to 75% lipid in the biomass, at up to 0.21 g lipid L−1 h−1) as the sole carbon source, but high lipid concentrations were also produced from xylose (36 to 45% lipid in biomass). Lipid production was low (15–19% lipid in biomass) with arabinose as sole carbon source and was lower than expected (30% lipid in biomass) when glucose, xylose and arabinose were provided simultaneously. The presence of arabinose and/or xylose in the medium increased the proportion of palmitic and linoleic acid and reduced the proportion of oleic acid in the fatty acids, compared to glucose-grown cells. High cell densities were obtained in both batch (37 g L−1, with 49% lipid in the biomass) and fed-batch (35 to 47 g L−1, with 50 to 75% lipid in the biomass) cultures. The highest proportion of lipid in the biomass was observed in cultures given nitrogen during the batch phase but none with the feed. However, carbohydrate consumption was incomplete when the feed did not contain nitrogen and the highest total lipid and best substrate consumption were observed in cultures which received a constant low nitrogen supply. Conclusions Lipid production in R. toruloides was lower from arabinose and mixed carbohydrates than from glucose

  12. Sorption studies of Cr(VI) from aqueous solution using bio-char as an adsorbent.

    PubMed

    Hyder, A H M G; Begum, Shamim A; Egiebor, Nosa O

    2014-01-01

    The characteristics of sorption of hexavalent chromium (Cr(VI)) onto bio-char derived from wood chips (spruce, pine, and fir) were evaluated as a function of pH, initial Cr(VI) concentration and bio-char dosage using synthetic wastewater in batch tests. The initial Cr(VI) concentrations were varied between 10 and 500 mg/L to investigate equilibrium, kinetics, and isotherms of the sorption process. About 100% of Cr(VI) was removed at pH 2 with initial Cr(VI) concentration of 10 mg/L using 4 g of bio-char after 5 hours of sorption reaction. The maximum sorption capacity of the bio-char was 1.717 mg/g for an initial Cr(VI) concentration of 500 mg/L after 5 hours. The sorption kinetics of total Cr onto bio-char followed the second-order kinetic model. The Langmuir isotherm model provided the best fit for total Cr sorption onto bio-char. The bio-char used is a co-product of a down draft gasifier that uses the derived syngas to produce electricity. Bio-char as a low cost adsorbent demonstrated promising results for removal of Cr(VI) from aqueous solution. The findings of this study would be useful in designing a filtration unit with bio-char in a full-scale water and wastewater treatment plant for the Cr(VI) removal from contaminated waters. PMID:24901621

  13. The effect of surface modification on heavy metal ion removal from water by carbon nanoporous adsorbent

    NASA Astrophysics Data System (ADS)

    Baniamerian, M. J.; Moradi, S. E.; Noori, A.; Salahi, H.

    2009-12-01

    In this work, chemically oxidized mesoporous carbon (COMC) with excellent lead adsorption performance was prepared by an acid surface modification method from mesoporous carbon (MC) by wet impregnation method. The structural order and textural properties of the mesoporous materials were studied by XRD, SEM, and nitrogen adsorption. The presence of carboxylic functional groups on the carbon surface was confirmed by FT-IR analysis. Batch adsorption experiments were conducted to study the effect of adsorbent dose, initial concentration and temperature for the removal of Pb(II) from aqueous systems. The adsorption was maximum for the initial pH in the range of 6.5-8.0. The kinetic data were best fitted to the pseudo-second order model. The adsorption of chemically oxidized mesoporous carbon to Pb(II) fits to the Langmuir model. The larger adsorption capacity of chemically oxidized mesoporous carbon for Pb(II) is mainly due to the oxygenous functional groups formed on the surface of COMC which can react with Pb(II) to form salt or complex deposited on the surface of MC.

  14. Heterocoagulated clay-derived adsorbents for phosphate decontamination from aqueous solution.

    PubMed

    Gan, Fangqun; Luo, Yufeng; Hang, Xiaoshuai; Zhao, Hongting

    2016-01-15

    A series of nanocomposite adsorbents were prepared by heterocoagulation of negatively charged delaminated montmorillonite (Mt) and positively charged synthetic layered double hydroxide (LDH) colloids with different LDH loading amounts. The mineralogy and physicochemical properties of the resulting nanocomposites were characterized. Their potential applications for phosphate (P) removal from aqueous solution, as a function of P concentration (2.5-200 mg/L), contact time (1 min-48 h) and pH (3-10), were evaluated by using batch adsorption modes. It was found that the adsorption data could be well described by both Freundlich and Langmuir isotherm models. The maximum adsorption capacity of three different LDH heterocoagulated montmorillonites (LDH-Mts) for P removal was found to increase with LDH loadings, reaching 12.6, 16.2 and 23.3 mg/g respectively; Adsorption kinetic data revealed that 90% of adsorption onto LDH-Mts was completed within 1 h (h) and the adsorption process could be well described by the pseudo-second-order model. These results demonstrated that heterocoagulation of Mt and LDH could preserve the adsorption capacity of LDH for P and enhance the stability of both clay minerals, and LDH-Mts could be effectively used as a potential promising filtration medium for P removal. PMID:26468604

  15. Characterization of cross-linked cellulosic ion-exchange adsorbents: 2. Protein sorption and transport.

    PubMed

    Angelo, James M; Cvetkovic, Aleksandar; Gantier, Rene; Lenhoff, Abraham M

    2016-03-18

    Adsorption behavior in the HyperCel family of cellulosic ion-exchange materials (Pall Corporation) was characterized using methods to assess, quantitatively and qualitatively, the dynamics of protein uptake as well as static adsorption as a function of ionic strength and protein concentration using several model proteins. The three exchangers studied all presented relatively high adsorptive capacities under low ionic strength conditions, comparable to commercially available resins containing polymer functionalization aimed at increasing that particular characteristic. The strong cation- and anion-exchange moieties showed higher sensitivity to increasing salt concentrations, but protein affinity on the salt-tolerant STAR AX HyperCel exchanger remained strong at ionic strengths normally used in downstream processing to elute material fully during ion-exchange chromatography. Very high uptake rates were observed in both batch kinetics experiments and time-series confocal laser scanning microscopy, suggesting low intraparticle transport resistances relative to external film resistance, even at higher bulk protein concentrations where the opposite is typically observed. Electron microscopy imaging of protein adsorbed phases provided additional insight into particle structure that could not be resolved in previous work on the bare resins. PMID:26905881

  16. Tamarind (Tamarindus indica) fruit shell carbon: A calcium-rich promising adsorbent for fluoride removal from groundwater.

    PubMed

    Sivasankar, V; Rajkumar, S; Murugesh, S; Darchen, A

    2012-07-30

    Tamarindus indica fruit shells (TIFSs) are naturally calcium rich compounds. They were impregnated with ammonium carbonate and then carbonized, leading to ammonium carbonate activated ACA-TIFS carbon. The resulting materials and carbon arising from virgin fruit shells V-TIFS were characterized and assayed as adsorbent for the removal of fluoride anions from groundwater. The fluoride scavenging ability of TIFS carbons was due to naturally dispersed calcium compounds. X-ray diffraction (XRD) showed that TIFS carbon contained a mixture of calcium oxalate and calcium carbonate. Batch studies on the fluoride removal efficiency of TIFS carbons with respect to contact time, pH, initial fluoride concentration, and co-ion interference were conducted. Applicability of various kinetic models (viz., pseudo-first-order, pseudo-second-order, intra-particle diffusion and Elovich) and sorption isotherms were tested for batch techniques. The fluoride removal capacity of TIFS carbons was found to be 91% and 83% at a pH of 7.05 for V-TIFS and ACA-TIFS carbons, respectively. The practical applicability of TIFS carbons using groundwater samples was approved. The fluoride removal was greater in groundwater without hydrogen carbonate ions than those containing these ions. The characterizations of fluoride unloaded and loaded TIFS carbons were done by SEM and XRD studies. PMID:22626627

  17. THE FINING BEHAVIOR OF SELECTIVELY BATCHED COMMERCIAL GLASSES

    EPA Science Inventory

    A re-melt at higher temperatures is underway to try and resolve a greater difference in fining behaviors between conventional and selective batching methods. Concentric granulation combines the two-granule system into a single-granule system with a core and crust of different ...

  18. Processing TOVS Polar Pathfinder data using the distributed batch controller

    NASA Astrophysics Data System (ADS)

    Duff, James; Salem, Kenneth M.; Schweiger, Axel; Livny, Miron

    1997-09-01

    The distributed batch controller (DBC) supports scientific batch data processing. Batch jobs are distributed by the DBC over a collection of computing resources. Since these resources may be widely scattered the DBC is well suited for collaborative research efforts whose resources may not be centrally located. The DBC provides its users with centralized monitoring and control of distributed batch jobs. Version 1 of the DBC is currently being used by the TOVS Polar Pathfinder project to generate Arctic atmospheric temperature and humidity profiles. Profile generating jobs are distributed and executed by the DBC on workstation clusters located at several sites across the US. This paper describes the data processing requirements of the TOVS Polar Pathfinder project, and how the DBC is being used to meet them. It also describes Version 2 of the DBC. DBC V2 is implemented in Java, and utilizes a number of advanced Java features such as threads and remote method invocation. It incorporates a number of functional enhancements. These include a flexible mechanism supporting interoperation of the DBC with a wider variety of execution resources and an improved user interface.

  19. 27 CFR 19.598 - Dump/batch records.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2014-04-01 2014-04-01 false Dump/batch records. 19.598 Section 19.598 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY ALCOHOL DISTILLED SPIRITS PLANTS Records and Reports Processing Records § 19.598...

  20. 27 CFR 19.598 - Dump/batch records.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false Dump/batch records. 19.598 Section 19.598 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT... gallons, the percentage of alcohol by volume and proof, and alcoholic flavoring materials in proof...

  1. 27 CFR 19.598 - Dump/batch records.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2012-04-01 2012-04-01 false Dump/batch records. 19.598 Section 19.598 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT... gallons, the percentage of alcohol by volume and proof, and alcoholic flavoring materials in proof...

  2. 7 CFR 58.728 - Cooking the batch.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Cooking the batch. 58.728 Section 58.728 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) REGULATIONS AND STANDARDS UNDER THE AGRICULTURAL MARKETING ACT OF 1946 AND...

  3. Continuous cellulosic bioethanol fermentation by cyclic fed-batch cocultivation.

    PubMed

    Jiang, He-Long; He, Qiang; He, Zhili; Hemme, Christopher L; Wu, Liyou; Zhou, Jizhong

    2013-03-01

    Cocultivation of cellulolytic and saccharolytic microbial populations is a promising strategy to improve bioethanol production from the fermentation of recalcitrant cellulosic materials. Earlier studies have demonstrated the effectiveness of cocultivation in enhancing ethanolic fermentation of cellulose in batch fermentation. To further enhance process efficiency, a semicontinuous cyclic fed-batch fermentor configuration was evaluated for its potential in enhancing the efficiency of cellulose fermentation using cocultivation. Cocultures of cellulolytic Clostridium thermocellum LQRI and saccharolytic Thermoanaerobacter pseudethanolicus strain X514 were tested in the semicontinuous fermentor as a model system. Initial cellulose concentration and pH were identified as the key process parameters controlling cellulose fermentation performance in the fixed-volume cyclic fed-batch coculture system. At an initial cellulose concentration of 40 g liter(-1), the concentration of ethanol produced with pH control was 4.5-fold higher than that without pH control. It was also found that efficient cellulosic bioethanol production by cocultivation was sustained in the semicontinuous configuration, with bioethanol production reaching 474 mM in 96 h with an initial cellulose concentration of 80 g liter(-1) and pH controlled at 6.5 to 6.8. These results suggested the advantages of the cyclic fed-batch process for cellulosic bioethanol fermentation by the cocultures. PMID:23275517

  4. Tier 3 batch system data locality via managed caches

    NASA Astrophysics Data System (ADS)

    Fischer, Max; Giffels, Manuel; Jung, Christopher; Kühn, Eileen; Quast, Günter

    2015-05-01

    Modern data processing increasingly relies on data locality for performance and scalability, whereas the common HEP approaches aim for uniform resource pools with minimal locality, recently even across site boundaries. To combine advantages of both, the High- Performance Data Analysis (HPDA) Tier 3 concept opportunistically establishes data locality via coordinated caches. In accordance with HEP Tier 3 activities, the design incorporates two major assumptions: First, only a fraction of data is accessed regularly and thus the deciding factor for overall throughput. Second, data access may fallback to non-local, making permanent local data availability an inefficient resource usage strategy. Based on this, the HPDA design generically extends available storage hierarchies into the batch system. Using the batch system itself for scheduling file locality, an array of independent caches on the worker nodes is dynamically populated with high-profile data. Cache state information is exposed to the batch system both for managing caches and scheduling jobs. As a result, users directly work with a regular, adequately sized storage system. However, their automated batch processes are presented with local replications of data whenever possible.

  5. Batch Studies of Sodium Tetraphenylborate Decomposition on Reduced Palladium Catalyst

    SciTech Connect

    Barnes, M.J.

    2001-02-13

    In these batch experiments we obtained preliminary information on palladium based catalytic decomposition of sodium tetraphenylborate (NaTPB). These preliminary data provide necessary data to design subsequent catalytic decomposition experiments for NaTPB using a continuous stirred tank reactor (CSTR).

  6. Comparison of neptunium sorption results using batch and column techniques

    SciTech Connect

    Triay, I.R.; Furlano, A.C.; Weaver, S.C.; Chipera, S.J.; Bish, D.L.

    1996-08-01

    We used crushed-rock columns to study the sorption retardation of neptunium by zeolitic, devitrified, and vitric tuffs typical of those at the site of the potential high-level nuclear waste repository at Yucca Mountain, Nevada. We used two sodium bicarbonate waters (groundwater from Well J-13 at the site and water prepared to simulate groundwater from Well UE-25p No. 1) under oxidizing conditions. It was found that values of the sorption distribution coefficient, Kd, obtained from these column experiments under flowing conditions, regardless of the water or the water velocity used, agreed well with those obtained earlier from batch sorption experiments under static conditions. The batch sorption distribution coefficient can be used to predict the arrival time for neptunium eluted through the columns. On the other hand, the elution curves showed dispersivity, which implies that neptunium sorption in these tuffs may be nonlinear, irreversible, or noninstantaneous. As a result, use of a batch sorption distribution coefficient to calculate neptunium transport through Yucca Mountain tuffs would yield conservative values for neptunium release from the site. We also noted that neptunium (present as the anionic neptunyl carbonate complex) never eluted prior to tritiated water, which implies that charge exclusion does not appear to exclude neptunium from the tuff pores. The column experiments corroborated the trends observed in batch sorption experiments: neptunium sorption onto devitrified and vitric tuffs is minimal and sorption onto zeolitic tuffs decreases as the amount of sodium and bicarbonate/carbonate in the water increases.

  7. Adaptation to high throughput batch chromatography enhances multivariate screening.

    PubMed

    Barker, Gregory A; Calzada, Joseph; Herzer, Sibylle; Rieble, Siegfried

    2015-09-01

    High throughput process development offers unique approaches to explore complex process design spaces with relatively low material consumption. Batch chromatography is one technique that can be used to screen chromatographic conditions in a 96-well plate. Typical batch chromatography workflows examine variations in buffer conditions or comparison of multiple resins in a given process, as opposed to the assessment of protein loading conditions in combination with other factors. A modification to the batch chromatography paradigm is described here where experimental planning, programming, and a staggered loading approach increase the multivariate space that can be explored with a liquid handling system. The iterative batch chromatography (IBC) approach is described, which treats every well in a 96-well plate as an individual experiment, wherein protein loading conditions can be varied alongside other factors such as wash and elution buffer conditions. As all of these factors are explored in the same experiment, the interactions between them are characterized and the number of follow-up confirmatory experiments is reduced. This in turn improves statistical power and throughput. Two examples of the IBC method are shown and the impact of the load conditions are assessed in combination with the other factors explored. PMID:25914370

  8. 21 CFR 211.188 - Batch production and control records.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 4 2010-04-01 2010-04-01 false Batch production and control records. 211.188 Section 211.188 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS: GENERAL CURRENT GOOD MANUFACTURING PRACTICE FOR FINISHED PHARMACEUTICALS Records...

  9. ORGANIC LOADING STUDY OF FULL-SCALE SEQUENCING BATCH REACTORS

    EPA Science Inventory

    The sequencing batch reactor (SBR) at Culver, Indiana, has two 440(sup 3) aeration basins that have received primary effluent on an alternating, fill-and-draw basis since May 1980. During normal SBR operation, liquid level variation and mixed liquor suspended solids (MLSS) concen...

  10. 21 CFR 211.188 - Batch production and control records.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 4 2012-04-01 2012-04-01 false Batch production and control records. 211.188 Section 211.188 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS: GENERAL CURRENT GOOD MANUFACTURING PRACTICE FOR FINISHED PHARMACEUTICALS Records...

  11. 21 CFR 211.188 - Batch production and control records.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 4 2011-04-01 2011-04-01 false Batch production and control records. 211.188 Section 211.188 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS: GENERAL CURRENT GOOD MANUFACTURING PRACTICE FOR FINISHED PHARMACEUTICALS Records...

  12. 21 CFR 211.188 - Batch production and control records.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 4 2013-04-01 2013-04-01 false Batch production and control records. 211.188 Section 211.188 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS: GENERAL CURRENT GOOD MANUFACTURING PRACTICE FOR FINISHED PHARMACEUTICALS Records...

  13. 21 CFR 211.188 - Batch production and control records.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 4 2014-04-01 2014-04-01 false Batch production and control records. 211.188 Section 211.188 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS: GENERAL CURRENT GOOD MANUFACTURING PRACTICE FOR FINISHED PHARMACEUTICALS Records...

  14. 40 CFR 63.1408 - Aggregate batch vent stream provisions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... non-combustion control device, whichever is less stringent, on a continuous basis. (2) The owner or... non-combustion control device, whichever is less stringent, on a continuous basis. (b) Alternative... from all aggregate batch vent streams in the compliance demonstration required for reactor...

  15. Removal of chemical oxygen demand from landfill leachate using cow-dung ash as a low-cost adsorbent.

    PubMed

    Kaur, Kamalpreet; Mor, Suman; Ravindra, Khaiwal

    2016-05-01

    The application of cow dung ash was assessed for the removal of organic contamination from the wastewater using landfill leachate of known Chemical Oxygen Demand (COD) concentration in batch mode. The effect of various parameters like adsorbents dose, time, pH and temperature was investigated. Results indicate that upto 79% removal of COD could be achieved using activated cow dung ash (ACA) at optimum temperature of 30°C at pH 6.0 using 20g/L dose in 120min, whereas cow dung ash (CA) shows 66% removal at pH 8.0 using 20g/L dose, also in 120min. Data also shows that ACA exhibited 11-13% better removal efficiency than CA. COD removal efficiency of various adsorbents was also compared and it was found that ACA offers significantly higher efficiency. Freundlich and Langmuir adsorption isotherms were also applied, which depicts good correlations (0.921 and 0.976) with the experimental data. Scanning electron microscope (SEM) images shows that after the activation, carbon particles disintegrate and surface of particles become more rough and porous, indicating the reason for high adsorption efficiency of ACA. Hence, ACA offers a cost-effective solution for the removal of organic contaminants from the wastewater and for the direct treatment of landfill leachate. PMID:26919299

  16. Kinetics and isotherm analysis of Tropaeoline 000 adsorption onto unsaturated polyester resin (UPR): a non-carbon adsorbent.

    PubMed

    Jain, Rajeev; Sharma, Pooja; Sikarwar, Shalini

    2013-03-01

    The presence of dyes in water is undesirable due to the toxicological impact of their entrance into the food chain. Owing to the recalcitrant nature of dyes to biological oxidation, a tertiary treatment like adsorption is required. In the present study, unsaturated polyester resin (UPR) has been used as a sorbent in the treatment of dye-contaminated water. Different concentrations of Tropaeoline 000 containing water were treated with UPR. The preliminary investigations were carried out by batch adsorption to examine the effects of pH, adsorbate concentration, adsorbent dosage, contact time, and temperature. A plausible mechanism for the ongoing adsorption process and thermodynamic parameters have also been obtained from Langmuir and Freundlich adsorption isotherm models. Thermodynamic parameter showed that the sorption process of Tropaeoline 000 onto activated carbon (AC) and UPR were feasible, spontaneous, and endothermic under studied conditions. The estimated values for (ΔG) are -10.48 × 10(3) and -6.098 × 10(3) kJ mol(-1) over AC and UPR at 303 K (30 °C), indicating towards a spontaneous process. The adsorption process followed pseudo-first-order model. The mass transfer property of the sorption process was studied using Lagergren pseudo-first-order kinetic models. The values of % removal and k (ad) for dye systems were calculated at different temperatures (303-323 K). The mechanism of the adsorption process was determined from the intraparticle diffusion model. PMID:22689095

  17. Polypyrrole/cobalt ferrite/multiwalled carbon nanotubes as an adsorbent for removing uranium ions from aqueous solutions.

    PubMed

    Liu, Qi; Zhu, Jiahui; Tan, Lichao; Jing, Xiaoyan; Liu, Jingyuan; Song, Dalei; Zhang, Hongsen; Li, Rumin; Emelchenko, G A; Wang, Jun

    2016-05-31

    A novel rod-like, dual-shell structural adsorbent of polypyrrole/cobalt ferrite/multiwalled carbon nanotubes (PPy/CoFe2O4/MWCNTs) was successfully synthesized by a hydrothermal method, which could easily separate uranium(vi) ions with an external magnetic field. The structure and morphology of PPy/CoFe2O4/MWCNTs were characterized by VSM, XRD, XPS TEM and FT-IR. The results proved that the dual-shell structure was obtained in which a shell of cobalt ferrite and polypyrrole formed around the MWCNTs core. In batch adsorption experiments, including pH, equilibrium time and temperature on uranium adsorption, were investigated. The main results show that the PPy/CoFe2O4/MWCNTs composite has a higher affinity towards the uptake of uranium(vi) from aqueous solutions. The highest adsorption capacity reached was 148.8 mg U per g at pH 7. A kinetic analysis showed that the adsorption process was best described by a pseudo-second-order kinetic model. The uranium sorption equilibrium data correlated well with the Langmuir sorption isotherm model in the thermodynamic analysis. 0.5 mol per L NaHCO3 was used as the desorbent and good adsorption properties were shown after the desorption procedures were repeated three times. Thus, PPy/CoFe2O4/MWCNTs was an excellent adsorbent for removing uranium(vi) ions. PMID:27169495

  18. Schiff base - Chitosan grafted L-monoguluronic acid as a novel solid-phase adsorbent for removal of congo red.

    PubMed

    Yuan, Bo; Qiu, Li-Gan; Su, Hong-Zhen; Cao, Cheng-Liang; Jiang, Ji-Hong

    2016-01-01

    A novel modified chitosan adsorbent (GL-SBCS) was synthesized by covalently grafting a Schiff base-chitosan (SBCS) onto the surface of l-monoguluronic acid. Physico-chemical investigation on the adsorption of congo red, an anionic azo dye by GL-SBCS has been carried out. The effect of different weight contents of chitosan in GL-SBCS composite, adsorbent dosage, initial pH and contract time were studied in detail using batch adsorption. Results showed that GL-SBCS exhibited better than normal CS and l-monoguluronic acid. Further investigation demonstrated that the adsorption pattern fitted well with the Langmuir model (R(2)>0.99) but less-satisfied the Freundlich model. Both ionic interaction as well as physical forces is responsible for binding of congo red with GL-SBCS as determined by zeta potential measurement Both sodium chloride and sodium dodecyl sulfate significantly influenced the adsorption process. SBCS would be a good method and resource to increase absorption efficiency for the removal of anionic dyes in a wastewater treatment process. PMID:26432372

  19. Cross-linking of succinate-grafted chitosan and its effect on the capability to adsorb Pb(II) ion

    NASA Astrophysics Data System (ADS)

    Masykur, Abu; Juari Santosa, Sri; Jumina, Dwi Siswanta dan

    2016-02-01

    The aim of this research was to improve the adsorption capacity of chitosan by modification of the chitosan using various cross-linking agents and followed by grafting using succinate anhydride. Succinate anhydride was grafted into chitosan that had been cross-linked using ethylene glycol di-glycidyl ether (EGDE), diethylene glycol diglycidyl ether (DEGDE) andbisphenolAdiglycidyl ether (BADGE) on the hydroxyl group of chitosan to yield Chit- EGDE-Suc, Chit-DEGDE-Suc, and Chit-BADGE-Suc, respectively. Modified chitosans were analyzed using FTIR and TG-DTA and then applied as adsorbents for Pb(II) ion. Adsorption was carried out in batch condition with a variation of solution pH, contact time, and concentration of Pb(II) in the solution. Adsorption ofPb(II) ion reached optimum condition at pH 5 and contact time of 120 minutes. Adsorption of Pb(II) ion on all of the adsorbents fit well the pseudo-second order kinetic equation. Adsorption capacities of Pb(II) on Chit-EGDE-Suc, Chit-DEGDE-SucdanChit-BADGE-Suc were 0.333, 0.388 and 0.898 mmolg-1, respectively, which mean that the adsorption of Chit-BADGE-Suc was the highest and followed by Chit- DEGDE-Suc and Chit-EGDE-Suc.

  20. Evaluating the long-term performance of low-cost adsorbents using small-scale adsorption column experiments.

    PubMed

    Callery, O; Healy, M G; Rognard, F; Barthelemy, L; Brennan, R B

    2016-09-15

    This study investigated a novel method of predicting the long-term phosphorus removal performance of large-scale adsorption filters, using data derived from short-term, small-scale column experiments. The filter media investigated were low-cost adsorbents such as aluminum sulfate drinking water treatment residual, ferric sulfate drinking water treatment residual, and fine and coarse crushed concretes. Small-bore adsorption columns were loaded with synthetic wastewater, and treated column effluent volume was plotted against the mass of phosphorus adsorbed per unit mass of filter media. It was observed that the curve described by the data strongly resembled that of a standard adsorption isotherm created from batch adsorption data. Consequently, it was hypothesized that an equation following the form of the Freundlich isotherm would describe the relationship between filter loading and media saturation. Moreover, the relationship between filter loading and effluent concentration could also be derived from this equation. The proposed model was demonstrated to accurately predict the performance of large-scale adsorption filters over a period of up to three months with a very high degree of accuracy. Furthermore, the coefficients necessary to produce said model could be determined from just 24 h of small-scale experimental data. PMID:27295617

  1. Preparation and Characterization of Chitosan/Feldspar Biohybrid as an Adsorbent: Optimization of Adsorption Process via Response Surface Modeling

    PubMed Central

    Yazdani, Maryam; Bahrami, Hajir; Arami, Mokhtar

    2014-01-01

    Chitosan/feldspar biobased beads were synthesized, characterized, and tested for the removal of Acid Black 1 dye from aquatic phases. A four-factor central composite design (CCD) accompanied by response surface modeling (RSM) and optimization was used to optimize the dye adsorption by the adsorbent (chitosan/feldspar composite) in 31 different batch experiments. Independent variables of temperature, pH, initial dye concentration, and adsorbent dose were used to change to coded values. To anticipate the responses, a quadratic model was applied. Analysis of variance (ANOVA) tested the significance of the process factors and their interactions. The adequacy of the model was investigated by the correlation between experimental and predicted data of the adsorption and the calculation of prediction errors. The results showed that the predicted maximum adsorption amount of 21.63 mg/g under the optimum conditions (pH 3, temperature 15°C, initial dye concentration 125 mg/L, and dose 0.2 g/50 mL) was close to the experimental value of 19.85 mg/g. In addition, the results of adsorption behaviors of the dye illustrated that the adsorption process followed the Langmuir isotherm model and the pseudo-second-order kinetic model. Langmuir sorption capacity was found to be 17.86 mg/g. Besides, thermodynamic parameters were evaluated and revealed that the adsorption process was exothermic and favourable. PMID:24587722

  2. Vibrational Studies of Adsorbate-Induced Reconstruction on Molybdenum Surfaces.

    NASA Astrophysics Data System (ADS)

    Lopinski, Gregory Peter

    Adsorbate-induced rearrangement of the substrate structure strongly modifies the adsorbate-substrate and adsorbate-adsorbate interactions, leading to the complex behavior observed in many chemisorption systems. In this thesis the H/Mo(211), O/Mo(211) and Na/Mo(100) systems have been studied using high resolution electron energy loss spectroscopy (HREELS) to observe vibrations of the adsorbed atoms. The vibrational data is correlated with observations of the long-range order probed by LEED as well as the work function changes induced by adsorption. Adsorbate -induced substrate reconstruction plays an important role in all three of these systems. Studies of the coadsorption systems O+H/Mo(211) and Na+O/Mo(100) indicate how these effects can influence interactions between adsorbates. For H/Mo(211), above 1ML a (1 x 1) to (1 x 2) transition is observed and attributed to modification of the substrate periodicity. Below 1ML, H atoms are bridge bonded and induce local distortions of the substrate. The transition to the (1 x 2) phase involves the ordering of these displacements and occupation of three-fold sites partially populated by conversion of the bridge bonded species. This conversion accounts for the sawtooth-like coverage dependence of the work function. The structural model proposed for this system is also supported by the desorption parameters and partial molar entropy extracted from adsorption isobars. Oxygen adsorption on Mo(211) involves the occupation of multiple binding sites, with both the long-range order and the local geometry of the adsorbate phases strongly temperature dependent. Coadsorption of low coverages of oxygen and hydrogen leads to segregation of the two adsorbates which can be understood in terms of a substrate-mediated repulsive interaction between O and H. For Na/Mo(100), the frequency of the Na-Mo symmetric stretch mode does not shift with coverage although the mode intensity is strongly coverage dependent. The absence of a frequency shift

  3. Batch and fixed-bed column studies for biosorption of Zn(II) ions onto pongamia oil cake (Pongamia pinnata) from biodiesel oil extraction.

    PubMed

    Shanmugaprakash, M; Sivakumar, V

    2015-12-01

    The present work, analyzes the potential of defatted pongamia oil cake (DPOC) for the biosorption of Zn(II) ions from aqueous solutions in the both batch and column mode. Batch experiments were conducted to evaluate the optimal pH, effect of adsorbent dosage, initial Zn(II) ions concentration and contact time. The biosorption equilibrium and kinetics data for Zn(II) ions onto the DPOC were studied in detail, using several models, among all it was found to be that, Freundlich and the second-order model explained the equilibrium data well. The calculated thermodynamic parameters had shown that the biosorption of Zn(II) ions was exothermic and spontaneous in nature. Batch desorption studies showed that the maximum Zn(II) recovery occurred, using 0.1 M EDTA. The Bed Depth Service Time (BDST) and the Thomas model was successfully employed to evaluate the model parameters in the column mode. The results indicated that the DPOC can be applied as an effective and eco-friendly biosorbent for the removal of Zn(II) ions in polluted wastewater. PMID:26366934

  4. [DSC and FTIR study of adsorbed lysozyme on hydrophobic surface].

    PubMed

    Lei, Zu-meng; Geng, Xin-peng; Dai, Li; Geng, Xin-du

    2008-09-01

    During a process of hen egg white lysozyme adsorption and folding on a moderately hydrophobic surface (PEG-600), the effects of salt((NH4)2SO4) concentrations, surface coverage and denaturant (guanidine hydrochloride, GuHCl) concentrations on thermal stability and the changes in the molecular conformation of adsorbed native and denatured lysozyme without aqueous solution were studied with a combination of differential scanning calorimetry (DSC) with FTIR spectroscopy. The results showed that temperature due to endothermic peaks was reduced and the disturbance increased at higher temperature with the increase in salt concentration and surface coverage of adsorbed protein. beta-Sheet and beta-Turn stucture increased while alpha-Helix structure decreased after the adsorption. The peaks corresponding to both C-C stretching frequency in 1400-1425 cm(-1) and amide I band frequency in 1650-1670 cm(-1) of adsorbed denatured lysozyme can be detected in FTIR spectra while that due to amide I band frequency of adsorbed native lysozyme almost can't be observed. Adsorption resulted in structural loss of adsorbed native lysozyme, whose performance was less stable. PMID:19093560

  5. High capacity cryogel-type adsorbents for protein purification.

    PubMed

    Singh, Naveen Kumar; Dsouza, Roy N; Grasselli, Mariano; Fernández-Lahore, Marcelo

    2014-08-15

    Cryogel bodies were modified to obtain epoxy groups by graft-copolymerization using both chemical and gamma irradiation initiation techniques. The free epoxy adsorbents were reacted further to introduce diethylaminoethanol (DEAE) functionalities. The resulting weak anion-exchange cryogel adsorbents showed dynamic binding capacities of ca. 27±3mg/mL, which was significantly higher than previously reported for this type of adsorbent material. Gamma irradiated grafting initiation showed a 4-fold higher capacity for proteins than chemical grafting initiation procedures. The phosphate capacity for these DEAE cryogels was 119mmol/L and also showed similar column efficiency as compared to commercial adsorbents. The large pores in the cryogel structure ensure convective transport of the molecules to active binding sites located on the polymer-grafted surface of cryogels. However, as cryogels have relatively large pores (10-100μm), the BET area available for surface activation is low, and consequently, the capacity of the cryogels is relatively low for biomolecules, especially when compared to commercial beaded adsorbents. Nevertheless, we have shown that gamma ray mediated surface grafting of cryogel matrices greatly enhance their functional and adsorptive properties. PMID:24980092

  6. Rifamycins Production by Amycolatopsis mediterranei in Batch and Repeated Batch Cultures Using Immobilized Cells in Alginate and Modified Alginate Beads

    NASA Astrophysics Data System (ADS)

    El-Enshasy, Hesham A.; Beshay, Usama I.; El-Diwany, Ahmed I.; Omar, Hoda M.; El-Kholy, Abdel Ghany E.; El-Najar, Rabab

    The production of rifamycins B and SV by Amycolatopsis mediterranei using immobilization technique was investigated. Alginate beads proved to be an alternative method for the production of rifamycin antibiotic as it has many advantage over using free cells such as it enables the operation at higher dilution rates without the danger of wash out, ease of handling and facilitates recycling or reverse of using microorganism. Different hardening agents were used to improve the stability of the beads and decrease cells escapement. Gum Arabic and gellan gum were used and the rate of rifamycin production increased by using gellan gum as hardening agent compared to pure alginate beads. The rifamycins B and SV increased from 685 to 810 and from 547.5 to 702 mg L-1, respectively by using gellan-gum modified beads compared to the non-treated beads. In repeated batch production, the beads were stable and no breaking of the gel beads was observed throughout the experiment time. The total amount of rifamycin B and SV during the five repeated batches (each of 144 h) reached 3360 and 2309 mg L-1, respectively. On reducing the batch time to only 72 h, the antibiotic production was not influenced and the total concentration of rifamycins B and SV for five batches was 3785 and 2393 mg L-1, respectively.

  7. Adsorption of lead ions on composite biopolymer adsorbent

    SciTech Connect

    Seki, Hideshi; Suzuki, Akira

    1996-04-01

    A fundamental study about the application of biopolymers to the recovery of lead from dilute solution was carried out. A membranous composite biopolymer adsorbent containing two kind of biopolymers, alginic acid (AA) and humic acid (HA), was prepared. HA, which has high solubility in water, was almost completely immobilized in the adsorbent by a combination of calcium alginate gel and activated carbon powder. A general model for complexation between divalent metal ions and acidic sites on biopolymers was applied to explain the adsorption mechanism of lead on the adsorbent (HA-M). The results showed that the complexation constants and the complexation capacities of lead-AA and lead-HA systems were scarcely influenced by immobilization.

  8. Method of recovering adsorbed liquid compounds from molecular sieve columns

    DOEpatents

    Burkholder, Harvey R.; Fanslow, Glenn E.

    1983-01-01

    Molecularly adsorbed volatile liquid compounds are recovered from molecular sieve adsorbent columns by directionally applying microwave energy to the bed of the adsorbent to produce a mixed liquid-gas effluent. The gas portion of the effluent generates pressure within the bed to promote the discharge of the effluent from the column bottoms. Preferably the discharged liquid-gas effluent is collected in two to three separate fractions, the second or intermediate fraction having a substantially higher concentration of the desorbed compound than the first or third fractions. The desorption does not need to be assisted by passing a carrier gas through the bed or by applying reduced pressure to the outlet from the bed.

  9. SERS effect of isonicotinic acid adsorbed on a copper electrode

    NASA Astrophysics Data System (ADS)

    Noda, Lucia K.; Sala, O.

    1987-11-01

    The surface enhanced Raman spectra (SERS) of isonicotinic acid adsorbed on a copper electrode were obtained in order to verify their dependence on the type of electrolyte solution, pH and applied potential. The results are discussed considering the most characteristic bands of the species (protonated or nonprotonated) in the ring nitrogen and in the carboxylic group. In specifically adsorbed electrolytes (Cl - and mainly I -) the completely protonated species is more stabilized on the electrode surface than it is in non-specifically adsorbed anions (ClO -4), because of the formation of ion pairs with the coadsorbed halide ions. For more negative potentials, even at low pH values, the spectra are characteristic of the nonprotonated species.

  10. Method of recovering adsorbed liquid compounds from molecular sieve columns

    DOEpatents

    Burkholder, H.R.; Fanslow, G.E.

    1983-12-20

    Molecularly adsorbed volatile liquid compounds are recovered from molecular sieve adsorbent columns by directionally applying microwave energy to the bed of the adsorbent to produce a mixed liquid-gas effluent. The gas portion of the effluent generates pressure within the bed to promote the discharge of the effluent from the column bottoms. Preferably the discharged liquid-gas effluent is collected in two to three separate fractions, the second or intermediate fraction having a substantially higher concentration of the desorbed compound than the first or third fractions. The desorption does not need to be assisted by passing a carrier gas through the bed or by applying reduced pressure to the outlet from the bed. 8 figs.

  11. Lotus Dust Mitigation Coating and Molecular Adsorber Coating

    NASA Technical Reports Server (NTRS)

    O'Connor, Kenneth M.; Abraham, Nithin S.

    2015-01-01

    NASA Goddard Space Flight Center has developed two unique coating formulations that will keep surfaces clean and sanitary and contain contaminants.The Lotus Dust Mitigation Coating, modeled after the self-cleaning, water-repellant lotus leaf, disallows buildup of dust, dirt, water, and more on surfaces. This coating, has been successfully tested on painted, aluminum, glass, silica, and some composite surfaces, could aid in keeping medical assets clean.The Molecular Adsorber Coating is a zeolite-based, sprayable molecular adsorber coating, designed to prevent outgassing in materials in vacuums. The coating works well to adsorb volatiles and contaminates in manufacturing and processing, such as in pharmaceutical production. The addition of a biocide would also aid in controlling bacteria levels.

  12. High-performances carbonaceous adsorbents for hydrogen storage

    NASA Astrophysics Data System (ADS)

    Zhao, Weigang; Fierro, Vanessa; Aylon, E.; Izquierdo, M. T.; Celzard, Alain

    2013-03-01

    Activated carbons (ACs) with controlled microporosity have been prepared and their H2 storage performances have been tested in a gravimetric device. Such adsorbents are natural Chinese anthracites chemically activated with alkaline hydroxides, NaOH or KOH. Outstanding total storage capacities of hydrogen, as high as 6.6wt.% equivalent to excess capacity of 6.2 wt.%, have been obtained at 4MPa for some of these adsorbents. These values of hydrogen adsorption are among the best, if not the highest, ever published so far in the open literature. They are well above those of some commercial materials, e.g. Maxsorb-3, considered as a reference of high-performance adsorbent for hydrogen adsorption. Such exceptional storage capacities may be ascribed to a higher volume of micropores (< 2nm).

  13. A high-capacity hydrophobic adsorbent for human serum albumin.

    PubMed

    Belew, M; Peterson, E A; Porath, J

    1985-12-01

    A simple method, based on salting out hydrophobic interaction chromatography, for the efficient removal of trace amounts of serum albumin from partially purified protein preparations is described. The method is also successfully applied for the purification of albumin from Cohn fraction IV, a by-product obtained from the commercial fractionation of human serum proteins by the ethanol precipitation procedure. About 70% of the adsorbed albumin can be eluted by buffer of low ionic strength and can thus be lyophilized directly, if required. The adsorbent can be used for several cycles of adsorption and desorption without affecting its selectivity or capacity. Its adsorption properties and capacity for serum albumin are compared with those of the commercially available adsorbent Blue Sepharose CL-6B. PMID:3879424

  14. Adsorbent selection for endosulfan removal from water environment.

    PubMed

    Sudhakar, Y; Dikshit, A K

    1999-01-01

    In the present study, an attempt was made to select a low cost adsorbing material for the removal of endosulfan [C,C'-(1,4,5,6,7,7-hexachloro-8,9,10- trinorborn-5-en-2,3-ylene)(dimethylsulphite)] from water. Various low cost adsorbents like wood charcoal, kimberlite tailings, silica, macro fungi sojar caju were tried with activated charcoal as reference material. The above materials were selected from various sources encompassing organic, inorganic, clayey, and biological sources. For the selection of suitable adsorbent for endosulfan uptake, maximum adsorption capacity (Qmax) was chosen as the parameter. Kinetic profiles of removal were generated for all the materials to assess the equilibrium time. Equilibrium studies were carried out for all materials to assess the adsorption equilibrium model that they followed. The model that gave the best correlation coefficient by linear regression analysis, was adopted for the calculation of Qmax of the corresponding adsorbent material. Using linearised forms of equilibrium models like Langmuir, BET, and Freundlich, maximum adsorptive capacities were determined. Activated charcoal showed the best adsorptive capacity with Qmax of 2.145 mg/g followed by wood charcoal 1.773 mg/g, sojar caju 1.575 mg/g, kimberlite tailings 0.8821 mg/g, and silica 0.3231 mg/g. Albeit activated charcoal gave better performance, it was not considered as a candidate material because of its high cost. Wood charcoal was the next best adsorbent with Qmax 1.773 mg/g. Therefore, wood charcoal was chosen as the best material for endosulfan removal. The study of physical and chemical characteristics of wood charcoal revealed that it is a potential adsorbent and can even be improved further. PMID:10048207

  15. Experimental characterization of adsorbed protein orientation, conformation, and bioactivity.

    PubMed

    Thyparambil, Aby A; Wei, Yang; Latour, Robert A

    2015-01-01

    Protein adsorption on material surfaces is a common phenomenon that is of critical importance in many biotechnological applications. The structure and function of adsorbed proteins are tightly interrelated and play a key role in the communication and interaction of the adsorbed proteins with the surrounding environment. Because the bioactive state of a protein on a surface is a function of the orientation, conformation, and accessibility of its bioactive site(s), the isolated determination of just one or two of these factors will typically not be sufficient to understand the structure-function relationships of the adsorbed layer. Rather a combination of methods is needed to address each of these factors in a synergistic manner to provide a complementary dataset to characterize and understand the bioactive state of adsorbed protein. Over the past several years, the authors have focused on the development of such a set of complementary methods to address this need. These methods include adsorbed-state circular dichroism spectropolarimetry to determine adsorption-induced changes in protein secondary structure, amino-acid labeling/mass spectrometry to assess adsorbed protein orientation and tertiary structure by monitoring adsorption-induced changes in residue solvent accessibility, and bioactivity assays to assess adsorption-induced changes in protein bioactivity. In this paper, the authors describe the methods that they have developed and/or adapted for each of these assays. The authors then provide an example of their application to characterize how adsorption-induced changes in protein structure influence the enzymatic activity of hen egg-white lysozyme on fused silica glass, high density polyethylene, and poly(methyl-methacrylate) as a set of model systems. PMID:25708632

  16. Experimental characterization of adsorbed protein orientation, conformation, and bioactivity

    PubMed Central

    Thyparambil, Aby A.; Wei, Yang; Latour, Robert A.

    2015-01-01

    Protein adsorption on material surfaces is a common phenomenon that is of critical importance in many biotechnological applications. The structure and function of adsorbed proteins are tightly interrelated and play a key role in the communication and interaction of the adsorbed proteins with the surrounding environment. Because the bioactive state of a protein on a surface is a function of the orientation, conformation, and accessibility of its bioactive site(s), the isolated determination of just one or two of these factors will typically not be sufficient to understand the structure–function relationships of the adsorbed layer. Rather a combination of methods is needed to address each of these factors in a synergistic manner to provide a complementary dataset to characterize and understand the bioactive state of adsorbed protein. Over the past several years, the authors have focused on the development of such a set of complementary methods to address this need. These methods include adsorbed-state circular dichroism spectropolarimetry to determine adsorption-induced changes in protein secondary structure, amino-acid labeling/mass spectrometry to assess adsorbed protein orientation and tertiary structure by monitoring adsorption-induced changes in residue solvent accessibility, and bioactivity assays to assess adsorption-induced changes in protein bioactivity. In this paper, the authors describe the methods that they have developed and/or adapted for each of these assays. The authors then provide an example of their application to characterize how adsorption-induced changes in protein structure influence the enzymatic activity of hen egg-white lysozyme on fused silica glass, high density polyethylene, and poly(methyl-methacrylate) as a set of model systems. PMID:25708632

  17. Extracting uranium from seawater: Promising AF series adsorbents

    SciTech Connect

    Das, Sadananda; Oyola, Y.; Mayes, Richard T.; Janke, Christopher James; Kuo, Li-Jung; Gill, Gary; Wood, Jordana; Dai, Sheng

    2015-11-02

    Here, a new family of high surface area polyethylene fiber adsorbents (AF series) was recently developed at the Oak Ridge National Laboratory (ORNL). The AF series of were synthesized by radiation-induced graft polymerization of acrylonitrile and itaconic acid (at different monomer/co-monomer mol ratios) onto high surface area polyethylene fibers. The degree of grafting (%DOG) of AF series adsorbents was found to be 154 354%. The grafted nitrile groups were converted to amidoxime groups by treating with hydroxylamine. The amidoximated adsorbents were then conditioned with 0.44M KOH at 80 C followed by screening at ORNL with simulated seawater spiked with 8 ppm uranium. Uranium adsorption capacity in simulated seawater screening ranged from 170-200 g-U/kg-ads irrespective of %DOG. A monomer/co-monomer mol ratio in the range of 7.57-10.14 seemed to be optimum for highest uranium loading capacity. Subsequently, the adsorbents were also tested with natural seawater at Pacific Northwest National Laboratory (PNNL) using flow-through exposure uptake experiments to determine uranium loading capacity with varying KOH conditioning time at 80 C. The highest adsorption capacity of AF1 measured after 56 days of marine testing was demonstrated as 3.9 g-U/kg-adsorbent and 3.2 g-U/kg-adsorbent for 1hr and 3hrs of KOH conditioning at 80 C, respectively. Based on capacity values of several AF1 samples, it was observed that changing KOH conditioning from 3hrs to 1hr at 80 C resulted in 22-27% increase in uranium loading capacity in seawater.

  18. Extracting uranium from seawater: Promising AF series adsorbents

    DOE PAGESBeta

    Das, Sadananda; Oyola, Y.; Mayes, Richard T.; Janke, Christopher James; Kuo, Li-Jung; Gill, Gary; Wood, Jordana; Dai, Sheng

    2015-11-02

    Here, a new family of high surface area polyethylene fiber adsorbents (AF series) was recently developed at the Oak Ridge National Laboratory (ORNL). The AF series of were synthesized by radiation-induced graft polymerization of acrylonitrile and itaconic acid (at different monomer/co-monomer mol ratios) onto high surface area polyethylene fibers. The degree of grafting (%DOG) of AF series adsorbents was found to be 154 354%. The grafted nitrile groups were converted to amidoxime groups by treating with hydroxylamine. The amidoximated adsorbents were then conditioned with 0.44M KOH at 80 C followed by screening at ORNL with simulated seawater spiked with 8more » ppm uranium. Uranium adsorption capacity in simulated seawater screening ranged from 170-200 g-U/kg-ads irrespective of %DOG. A monomer/co-monomer mol ratio in the range of 7.57-10.14 seemed to be optimum for highest uranium loading capacity. Subsequently, the adsorbents were also tested with natural seawater at Pacific Northwest National Laboratory (PNNL) using flow-through exposure uptake experiments to determine uranium loading capacity with varying KOH conditioning time at 80 C. The highest adsorption capacity of AF1 measured after 56 days of marine testing was demonstrated as 3.9 g-U/kg-adsorbent and 3.2 g-U/kg-adsorbent for 1hr and 3hrs of KOH conditioning at 80 C, respectively. Based on capacity values of several AF1 samples, it was observed that changing KOH conditioning from 3hrs to 1hr at 80 C resulted in 22-27% increase in uranium loading capacity in seawater.« less

  19. [Analysis of the transcriptional profiling of cell cycle regulatory networks of recombinant Chinese hamster ovary cells in batch and fed-batch cultures].

    PubMed

    Liu, Xingmao; Ye, Lingling; Liu, Hong; Li, Shichong; Wang, Qiwei; Wu, Benchuan; Chen, Zhaolie

    2011-08-01

    In the light of Chinese hamster ovary (CHO) cell line 11G-S expressing human recombinant pro-urokinase, the differences of gene expression levels of the cells in different growth phases in both batch and fed-batch cultures were revealed by using gene chip technology. Then, based on the known cell cycle regulatory networks, the transcriptional profiling of the cell cycle regulatory networks of the cells in batch and fed-batch cultures was analyzed by using Genmapp software. Among the approximate 19 191 target genes in gene chip, the number of down-regulated genes was more than those of up-regulated genes of the cells in both batch and fed-batch cultures. The number of down-regulated genes of the cells in the recession phase in fed-batch culture was much more than that of the cells in batch culture. Comparative transcriptional analysis of the key cell cycle regulatory genes of the cells in both culture modes indicated that the cell proliferation and cell viability of the cells in both batch and fed-batch cultures were mainly regulated through down-regulating Cdk6, Cdk2, Cdc2a, Ccne1, Ccne2 genes of CDKs, Cyclin and CKI family and up-regulating Smad4 gene. PMID:22097809

  20. Surface characterization of adsorbed asphaltene on a stainless steel surface

    NASA Astrophysics Data System (ADS)

    Abdallah, W. A.; Taylor, S. D.

    2007-05-01

    X-ray photoelectron spectroscopy was used to characterize a single layer of adsorbed asphaltene on a metallic surface. The deposits were created by immersing a stainless steel disc into a dilute asphaltene solution with either toluene or dichloromethane as the solvent, although the toluene solution allowed for better control of the adsorbed asphaltene layer and less atmospheric oxygen contamination. The analyses for C 1s, S 2p3/2, N 1s and O 1s photoemission peaks indicated that different functional groups are present in the asphaltene layer including carboxylic, pyrrolic, pyridininc, thiophenic and sulfite, with slight differences in their binding energies.

  1. AQUATIC PHOTOLYSIS OF OXY-ORGANIC COMPOUNDS ADSORBED ON GOETHITE.

    USGS Publications Warehouse

    Goldberg, Marvin C.

    1985-01-01

    Organic materials that will not absorb light at wavelengths longer than 295 nanometers (the solar wavelength cutoff) may nevertheless, undergo electron transfer reactions initiated by light. These reactions occur when the organic materials are adsorbed as ligand complexes to the surface of iron oxy-hydroxide (goethite). The adsorbed materials can be either inner or outer coordination sphere complexes. Goethite was chosen as the iron oxyhydroxide surface because it has the highest thermodynamic stability of any of the oxyhydroxides in water and it can be synthesized easily, with high purity.

  2. Adsorbed liposome deformation studied with quartz crystal microbalance

    NASA Astrophysics Data System (ADS)

    Reviakine, Ilya; Gallego, Marta; Johannsmann, Diethelm; Tellechea, Edurne

    2012-02-01

    Deformation of surface-adsorbed liposomes is an important parameter that governs the kinetics of their transformations, but one that is very difficult to measure in the case of nm-size liposomes. We investigate the deformation of dimyristoyl phosphatidyl choline liposomes by quartz crystal microbalance (QCM) as a function of temperature and show that it follows the dependence of this lipid's bending modulus on temperature, as expected from theoretical considerations. To corroborate our approach, we model QCM response from adsorbed liposomes by explicitly considering their shape and mechanical properties.

  3. Carbon adsorbents from products of solid fuel processing

    SciTech Connect

    Pokonova, Yu.V.; Grabovskii, A.I.

    1995-01-10

    Total shale phenols (mixture of alkylresorcinols) or their solution in commercial-grade furfural can be used for forming carbon adsorbents with high mechanical strength (up to 97%), high microporosity (up to 0.41 cm{sup 3}{center_dot}cm{sup -3}), and higher sorption capacity. Samples with medium burnout exhibit higher selectivity (than those molded from conventional wood tar) in the recovery of noble metals from multicomponent metal salt solutions. In these parameters they surpass commercial adsorbents as well. Samples with low burnout exhibit high selectivity and separation ability with respect to gas mixtures.

  4. Adsorbed water and CO on Pt electrode modified with Ru

    NASA Astrophysics Data System (ADS)

    Futamata, Masayuki; Luo, Liqiang

    Highly sensitive ATR-SEIRA spectroscopy was exploited to elucidate water, CO and electrolyte anions adsorbed on the Ru modified Pt film electrode. CO on Ru domains was oxidized below ca. +0.3 V, followed by pronounced water adsorption. Since the oxidation potential of CO on Pt domain was significantly reduced compared to bare Pt, these water molecules on Ru obviously prompt CO oxidation on adjacent Pt surface as consistent with the bifunctional mechanism. Diffusion of adsorbate from Ru to Pt surfaces was indicated in dilute CH 3OH solution by spectral changes with potential.

  5. Structural characterization of adsorbed helical and beta-sheet peptides

    NASA Astrophysics Data System (ADS)

    Samuel, Newton Thangadurai

    Adsorbed peptides on surfaces have potential applications in the fields of biomaterials, tissue engineering, peptide microarrays and nanobiotechnology. The surface region, the "biomolecular interface" between a material and the biological environment, plays a crucial role in these applications. As a result, characterization of adsorbed peptide structure, especially with respect to identity, concentration, spatial distribution, conformation and orientation, is important. The present research employs NEXAFS (near-edge X-ray absorption fine structure spectroscopy) and SFG (sum frequency generation spectroscopy) to provide information about the adsorbed peptide structure. Soft X-ray NEXAFS is a synchrotron-based technique which typically utilizes polarized X-rays to interrogate surfaces under ultra-high vacuum conditions. SFG is a non-linear optical technique which utilizes a combination of a fixed visible and a tunable infrared laser beams to generate a surface-vibrational spectrum of surface species. SFG has the added advantage of being able to directly analyze the surface-structure at the solid-liquid interface. The main goals of the present research were twofold: characterize the structure of adsorbed peptides (1) ex situ using soft X-ray NEXAFS, and (2) in situ using non-linear laser spectroscopy (SFG). Achieving the former goal involved first developing a comprehensive characterization of the carbon, nitrogen and oxygen k-edge NEXAFS spectra for amino acids, and then using a series of helical and beta-sheet peptides to demonstrate the sensitivity of polarization-dependent NEXAFS to secondary structure of adsorbed peptides. Characterizing the structure of adsorbed peptides in situ using SFG involved developing a model system to probe the solid-liquid interface in situ; demonstrating the ability to probe the molecular interactions and adsorbed secondary structure; following the time-dependent ordering of the adsorbed peptides; and establishing the ability to obtain

  6. Affinity Adsorbents Based on Carriers Activated by Epoxy-compounds

    NASA Astrophysics Data System (ADS)

    Klyashchitskii, B. A.; Kuznetsov, P. V.

    1984-10-01

    The review is devoted to the synthesis and applications of affinity adsorbents based on carriers activated by epoxy-compounds. The methods for the introduction of epoxy-groups into carriers of different chemical types are discussed and conditions for the immobilisation of three-dimensional spacers and low-molecular-weight and polymeric ligands on carriers containing epoxy-groups are considered. Data are presented on the properties and applications of adsorbents of this type in affinity chromatography. The bibliography includes 144 references.

  7. Hydrogen molecule on lithium adsorbed graphene: A DFT study

    NASA Astrophysics Data System (ADS)

    Kaur, Gagandeep; Gupta, Shuchi; Gaganpreet, Dharamvir, Keya

    2016-05-01

    Electronic structure calculations for the adsorption of molecular hydrogen on lithium (Li) decorated and pristine graphene have been studied systematically using SIESTA code [1] within the framework of the first-principle DFT under the Perdew-Burke-Ernzerhof (PBE) form of the generalized gradient approximation (GGA)[2], including spin polarization. The energy of adsorption of hydrogen molecule on graphene is always enhanced by the presence of co-adsorbed lithium. The most efficient adsorption configuration is when H2 is lying parallel to lithium adsorbed graphene which is in contrast to its adsorption on pristine graphene (PG) where it prefers perpendicular orientation.

  8. 21 CFR 111.255 - What is the requirement to establish a batch production record?

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION CURRENT GOOD MANUFACTURING PRACTICE IN MANUFACTURING, PACKAGING, LABELING, OR HOLDING OPERATIONS FOR DIETARY SUPPLEMENTS Production and Process Control... batch of a dietary supplement; (b) Your batch production record must include complete...

  9. Integrated system for temperature-controlled fast protein liquid chromatography comprising improved copolymer modified beaded agarose adsorbents and a travelling cooling zone reactor arrangement.

    PubMed

    Müller, Tobias K H; Cao, Ping; Ewert, Stephanie; Wohlgemuth, Jonas; Liu, Haiyang; Willett, Thomas C; Theodosiou, Eirini; Thomas, Owen R T; Franzreb, Matthias

    2013-04-12

    An integrated approach to temperature-controlled chromatography, involving copolymer modified agarose adsorbents and a novel travelling cooling zone reactor (TCZR) arrangement, is described. Sepharose CL6B was transformed into a thermoresponsive cation exchange adsorbent (thermoCEX) in four synthetic steps: (i) epichlorohydrin activation; (ii) amine capping; (iii) 4,4'-azobis(4-cyanovaleric acid) immobilization; and 'graft from' polymerization of poly(N-isopropylacrylamide-co-N-tert-butylacrylamide-co-acrylic acid-co-N,N'-methylenebisacrylamide). FT-IR, (1)H NMR, gravimetry and chemical assays allowed precise determination of the adsorbent's copolymer composition and loading, and identified the initial epoxy activation step as a critical determinant of 'on-support' copolymer loading, and in turn, protein binding performance. In batch binding studies with lactoferrin, thermoCEX's binding affinity and maximum adsorption capacity rose smoothly with temperature increase from 20 to 50 °C. In temperature shifting chromatography experiments employing thermoCEX in thermally jacketed columns, 44-51% of the lactoferrin adsorbed at 42 °C could be desorbed under binding conditions by cooling the column to 22 °C, but the elution peaks exhibited strong tailing. To more fully exploit the potential of thermoresponsive chromatography adsorbents, a new column arrangement, the TCZR, was developed. In TCZR chromatography, a narrow discrete cooling zone (special assembly of copper blocks and Peltier elements) is moved along a bespoke fixed-bed separation columnfilled with stationary phase. In tests with thermoCEX, it was possible to recover 65% of the lactoferrin bound at 35 °C using 8 successive movements of the cooling zone at a velocity of 0.1mm/s; over half of the recovered protein was eluted in the first peak in more concentrated form than in the feed. Intra-particle diffusion of desorbed protein out of the support pores, and the ratio between the velocities of the cooling

  10. Characterization of carbonated tricalcium silicate and its sorption capacity for heavy metals: a micron-scale composite adsorbent of active silicate gel and calcite.

    PubMed

    Chen, Quanyuan; Hills, Colin D; Yuan, Menghong; Liu, Huanhuan; Tyrer, Mark

    2008-05-01

    Adsorption-based processes are widely used in the treatment of dilute metal-bearing wastewaters. The development of versatile, low-cost adsorbents is the subject of continuing interest. This paper examines the preparation, characterization and performance of a micro-scale composite adsorbent composed of silica gel (15.9 w/w%), calcium silicate hydrate gel (8.2 w/w%) and calcite (75.9 w/w%), produced by the accelerated carbonation of tricalcium silicate (C(3)S, Ca(3)SiO(5)). The Ca/Si ratio of calcium silicate hydrate gel (C-S-H) was determined at 0.12 (DTA/TG), 0.17 ((29)Si solid-state MAS/NMR) and 0.18 (SEM/EDS). The metals-retention capacity for selected Cu(II), Pb(II), Zn(II) and Cr(III) was determined by batch and column sorption experiments utilizing nitrate solutions. The effects of metal ion concentration, pH and contact time on binding ability was investigated by kinetic and equilibrium adsorption isotherm studies. The adsorption capacity for Pb(II), Cr(III), Zn(II) and Cu(II) was found to be 94.4 mg/g, 83.0 mg/g, 52.1 mg/g and 31.4 mg/g, respectively. It is concluded that the composite adsorbent has considerable potential for the treatment of industrial wastewater containing heavy metals. PMID:17950999

  11. Use of Ni/NixB Nanoparticles as a Novel Adsorbent for the Preconcentration of Mercury Species prior to Cold Vapor-Atomic Fluorescence Spectrometric Determination.

    PubMed

    Yayayürük, Onur; Henden, Emür

    2016-01-01

    A selective matrix separation/enrichment method, utilizing a simple batch procedure with nickel/nickel boride (Ni/NixB) nanoparticles was proposed for the determination of inorganic mercury(II), Hg(2+) and methyl mercury(I), CH3Hg(+) in waters prior to cold vapor-atomic fluorescence spectrometry (CV-AFS). The Ni/NixB nanoparticles, were synthesized by the chemical reduction of Ni(II) to Ni/NixB. The novel adsorbent was selective to Hg(2+) and CH3Hg(+) species between pH values of 4 - 10. Both of the mercury species were recovered from the adsorbent using 1.0 mol L(-1) hot HNO3 with high efficiency. It was observed that the adsorbent selectively removed Hg(2+) and CH3Hg(+) from the bulk solution in the presence of several competitor ions (As(3+), Sb(3+), Pb(2+), Zn(2+), Cu(2+), Cd(2+) and Fe(3+)) with ≥96% adsorption. The limit of detection (3σ above blank) was found to be 1.8 ng L(-1) with a preconcentration factor of 20. The validation of the method was tested through spike recovery experiments with several water samples (tap and seawater) at μg L(-1) concentration levels, and all recovery values were found to vary between 95 and 105%. PMID:27506713

  12. Poly(itaconic acid)-grafted chitosan adsorbents with different cross-linking for Pb(II) and Cd(II) uptake.

    PubMed

    Kyzas, George Z; Siafaka, Panoraia I; Lambropoulou, Dimitra A; Lazaridis, Nikolaos K; Bikiaris, Dimitrios N

    2014-01-14

    Two novel chitosan (CS) adsorbents were prepared in powder form, after modification with the grafting of itaconic acid (CS-g-IA) and cross-linking with either glutaraldehyde (CS-g-IA(G)) or epichlorohydrin (CS-g-IA(E)). Their adsorption properties were evaluated in batch experiments for Cd(II) or Pb(II) uptake. Characterization techniques were applied to the prepared adsorbents as swelling experiments, TGA, SEM, XRD, and FTIR. Adsorption mechanisms were suggested for different pH conditions. Various adsorption parameters were determined as the effect of pH, contact time, and temperature. The maximum adsorption capacities for Cd(II) uptake were 405 and 331 mg/g for CS-g-IA(G) and CS-g-IA(E), respectively, revealing the capacity enhancement after grafting (124 and 92 mg/g were the respective values before grafting, respectively). A similar grafting effect was observed for Pb(II) uptake, proving its adsorption effectiveness on the CS backbone. The reuse of adsorbents was tested with 20 adsorption-desorption cycles. PMID:24011255

  13. Sorting Olive Batches for the Milling Process Using Image Processing.

    PubMed

    Aguilera Puerto, Daniel; Martínez Gila, Diego Manuel; Gámez García, Javier; Gómez Ortega, Juan

    2015-01-01

    The quality of virgin olive oil obtained in the milling process is directly bound to the characteristics of the olives. Hence, the correct classification of the different incoming olive batches is crucial to reach the maximum quality of the oil. The aim of this work is to provide an automatic inspection system, based on computer vision, and to classify automatically different batches of olives entering the milling process. The classification is based on the differentiation between ground and tree olives. For this purpose, three different species have been studied (Picudo, Picual and Hojiblanco). The samples have been obtained by picking the olives directly from the tree or from the ground. The feature vector of the samples has been obtained on the basis of the olive image histograms. Moreover, different image preprocessing has been employed, and two classification techniques have been used: these are discriminant analysis and neural networks. The proposed methodology has been validated successfully, obtaining good classification results. PMID:26147729

  14. Empirical State Error Covariance Matrix for Batch Estimation

    NASA Technical Reports Server (NTRS)

    Frisbee, Joe

    2015-01-01

    State estimation techniques effectively provide mean state estimates. However, the theoretical state error covariance matrices provided as part of these techniques often suffer from a lack of confidence in their ability to describe the uncertainty in the estimated states. By a reinterpretation of the equations involved in the weighted batch least squares algorithm, it is possible to directly arrive at an empirical state error covariance matrix. The proposed empirical state error covariance matrix will contain the effect of all error sources, known or not. This empirical error covariance matrix may be calculated as a side computation for each unique batch solution. Results based on the proposed technique will be presented for a simple, two observer and measurement error only problem.

  15. Plutonium immobilization ceramic feed batching component test report

    SciTech Connect

    Erickson, S.A.

    1999-10-04

    The Plutonium Immobilization Facility will encapsulate plutonium in ceramic pucks and seal the pucks inside welded cans. Remote equipment will place these cans in magazines and the magazines in a Defense Waste Processing Facility (DWPF) canister. The DWPF will fill the canister with high level waste glass for permanent storage. Ceramic feed batching (CFB) is one of the first process steps involved with first stage plutonium immobilization. The CFB step will blend plutonium oxide powder before it is combined with other materials to make pucks. This report discusses the Plutonium Immobilization CFB process preliminary concept (including a process block diagram), batch splitting component test results, CFB development areas, and FY 1999 and 2000 CFB program milestones.

  16. Sorting Olive Batches for the Milling Process Using Image Processing

    PubMed Central

    Puerto, Daniel Aguilera; Martínez Gila, Diego Manuel; Gámez García, Javier; Gómez Ortega, Juan

    2015-01-01

    The quality of virgin olive oil obtained in the milling process is directly bound to the characteristics of the olives. Hence, the correct classification of the different incoming olive batches is crucial to reach the maximum quality of the oil. The aim of this work is to provide an automatic inspection system, based on computer vision, and to classify automatically different batches of olives entering the milling process. The classification is based on the differentiation between ground and tree olives. For this purpose, three different species have been studied (Picudo, Picual and Hojiblanco). The samples have been obtained by picking the olives directly from the tree or from the ground. The feature vector of the samples has been obtained on the basis of the olive image histograms. Moreover, different image preprocessing has been employed, and two classification techniques have been used: these are discriminant analysis and neural networks. The proposed methodology has been validated successfully, obtaining good classification results. PMID:26147729

  17. Jute batching oil: a tumor promoter on mouse skin

    SciTech Connect

    Mehrotra, N.K.; Kumar, S.; Agarwal, R.; Antony, M.

    1987-02-01

    A mineral oil essentially used in the jute industry for the batching of jute fibers, and earlier reported to be nontumorigenic on mouse skin, has been found to be a tumor promoter following a two-stage mouse-skin bioassay protocol. The types of tumors developed after initiation with a single dose of urethane or 3-methylcholanthrene (subcutaneously), followed by repeated skin painting with jute batching oil (JBO) included benign papillomas, keratoacanthomas, and fibrosarcomas. Chemical analysis of this oil indicated the total aromatic content was 11.71% and the amount of fluoranthene, pyrene, chrysene, and triphenylene was in the range of 192.54 to 227.79 mg/kg in the test sample. The underlying biochemical mechanism for the tumor-promoting effect of JBO seemed to operate through a different pathway rather than involving the induction of cytochrome-dependent monoxygenase and N-demethylase activities in the tissue.

  18. Minimizing makespan on parallel machines with batch arrivals

    NASA Astrophysics Data System (ADS)

    Chung, Tsui-Ping; Liao, Ching-Jong; Lin, Chien-Hung

    2012-04-01

    Most studies in the scheduling literature assume that jobs arrive at time zero, while some studies assume that jobs arrive individually at non-zero times. However, both assumptions may not be valid in practice because jobs usually arrive in batches. In this article, a scheduling model for an identical parallel machine problem with batch arrivals is formulated. Because of the NP-hardness of the problem, a heuristic based on a simplified version of lexicographical search is proposed. To verify the heuristic, two lower bounding schemes are developed, where one lower bound is tight, and the list scheduling heuristic is compared. Extensive computational experiments demonstrate that the proposed heuristic is quite efficient in obtaining near optimal solution with an average error of less than 1.58%. The percentage improvement (from the lower bound) of the heuristic solution on the solution by the list scheduling is as large as 31.68.

  19. A review of the Lasnet batch job system

    SciTech Connect

    Busby, L.

    1993-01-13

    The authors installed the McGill-DNQS job queuing system on their network of Sun Sparc and HP7x0 Unix workstations. These machines support interactive use as well as cpu-intensive batch jobs. After three months of operation they are generally very pleased with the system. This paper covers the decisions they made about installation, configuration, and operation. It details the successes and failures so far, and discusses future plans.

  20. Batch Production of Micron-scale Backlighter Targets

    NASA Astrophysics Data System (ADS)

    Arthur, G.

    2016-04-01

    The fabrication of micron-scale backlighter targets is described. Traditionally laser targets have been fabricated using conventional machining or coarse etching processes and have been produced in quantities of 10s to low 100s. The processes described herein allow batch production with numbers in the 1000s. In addition, the Micro-Electro-Mechanical System (MEMS) fabrication techniques used allow much finer tolerances and more accurate placement of the various components relative to each other.

  1. Simulation of continuous and batch hydrolysis of willow

    SciTech Connect

    Zacchi, G.; Dahlbom, J.; Scott, C.D.

    1986-01-01

    The influence of product and enzyme concentrations on the kinetics of the enzymic hydrolysis of alkali-pretreated willow is studied. The hydrolysis was performed in a UF-membrane reactor in which the product concentration was kept constant. An empirical 4-parameter rate equation that gives a good correlation to both continuous and batch hydrolysis data is presented. The model comprises the effects of enzyme concentration and product inhibition. (Refs. 11).

  2. Fed-batch cultivation of Cellulomonas on sugarcane bagasse pith

    SciTech Connect

    Rodriguez, H.; Enriquez, A.

    1985-02-01

    A high biomass concentration (19.9 g/L) was obtained with the fed-batch cultivation of Cellulomonas on pretreated sugarcane bagasse pith. Similar results in biomass concentration, yield, and substrate consumption were obtained with the discontinuous feed of bagasse as with discontinuous feed supplemented with a partial continuous addition of salts. Two or more growth phases were detected, probably caused by the differential utilization of bagasse components. An acceptably low content of bagasse components remained in the biomass after separation.

  3. Analyzing data flows of WLCG jobs at batch job level

    NASA Astrophysics Data System (ADS)

    Kuehn, Eileen; Fischer, Max; Giffels, Manuel; Jung, Christopher; Petzold, Andreas

    2015-05-01

    With the introduction of federated data access to the workflows of WLCG, it is becoming increasingly important for data centers to understand specific data flows regarding storage element accesses, firewall configurations, as well as the scheduling of batch jobs themselves. As existing batch system monitoring and related system monitoring tools do not support measurements at batch job level, a new tool has been developed and put into operation at the GridKa Tier 1 center for monitoring continuous data streams and characteristics of WLCG jobs and pilots. Long term measurements and data collection are in progress. These measurements already have been proven to be useful analyzing misbehaviors and various issues. Therefore we aim for an automated, realtime approach for anomaly detection. As a requirement, prototypes for standard workflows have to be examined. Based on measurements of several months, different features of HEP jobs are evaluated regarding their effectiveness for data mining approaches to identify these common workflows. The paper will introduce the actual measurement approach and statistics as well as the general concept and first results classifying different HEP job workflows derived from the measurements at GridKa.

  4. SLUDGE BATCH 4 SIMULANT FLOWSHEET STUDIES: PHASE II RESULTS

    SciTech Connect

    Stone, M; David Best, D

    2006-09-12

    The Defense Waste Processing Facility (DWPF) will transition from Sludge Batch 3 (SB3) processing to Sludge Batch 4 (SB4) processing in early fiscal year 2007. Tests were conducted using non-radioactive simulants of the expected SB4 composition to determine the impact of varying the acid stoichiometry during the Sludge Receipt and Adjustment Tank (SRAT) process. The work was conducted to meet the Technical Task Request (TTR) HLW/DWPF/TTR-2004-0031 and followed the guidelines of a Task Technical and Quality Assurance Plan (TT&QAP). The flowsheet studies are performed to evaluate the potential chemical processing issues, hydrogen generation rates, and process slurry rheological properties as a function of acid stoichiometry. Initial SB4 flowsheet studies were conducted to guide decisions during the sludge batch preparation process. These studies were conducted with the estimated SB4 composition at the time of the study. The composition has changed slightly since these studies were completed due to changes in the sludges blended to prepare SB4 and the estimated SB3 heel mass. The following TTR requirements were addressed in this testing: (1) Hydrogen and nitrous oxide generation rates as a function of acid stoichiometry; (2) Acid quantities and processing times required for mercury removal; (3) Acid quantities and processing times required for nitrite destruction; and (4) Impact of SB4 composition (in particular, oxalate, manganese, nickel, mercury, and aluminum) on DWPF processing (i.e. acid addition strategy, foaming, hydrogen generation, REDOX control, rheology, etc.).

  5. 21 CFR 111.260 - What must the batch record include?

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ..., LABELING, OR HOLDING OPERATIONS FOR DIETARY SUPPLEMENTS Production and Process Control System: Requirements... record must include the following: (a) The batch, lot, or control number: (1) Of the finished batch of... that quality control personnel: (1) Reviewed the batch production record, including: (i) Review of...

  6. 40 CFR 63.1407 - Non-reactor batch process vent provisions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 12 2014-07-01 2014-07-01 false Non-reactor batch process vent... Resins § 63.1407 Non-reactor batch process vent provisions. (a) Emission standards. (1) Owners or operators of non-reactor batch process vents located at new or existing affected sources with 0.25 tons...

  7. 40 CFR 63.1407 - Non-reactor batch process vent provisions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 12 2013-07-01 2013-07-01 false Non-reactor batch process vent... Resins § 63.1407 Non-reactor batch process vent provisions. (a) Emission standards. (1) Owners or operators of non-reactor batch process vents located at new or existing affected sources with 0.25 tons...

  8. 40 CFR 63.1407 - Non-reactor batch process vent provisions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 12 2012-07-01 2011-07-01 true Non-reactor batch process vent... § 63.1407 Non-reactor batch process vent provisions. (a) Emission standards. (1) Owners or operators of non-reactor batch process vents located at new or existing affected sources with 0.25 tons per year...

  9. 40 CFR 63.1407 - Non-reactor batch process vent provisions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 11 2011-07-01 2011-07-01 false Non-reactor batch process vent... § 63.1407 Non-reactor batch process vent provisions. (a) Emission standards. (1) Owners or operators of non-reactor batch process vents located at new or existing affected sources with 0.25 tons per year...

  10. 40 CFR 63.1407 - Non-reactor batch process vent provisions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 11 2010-07-01 2010-07-01 true Non-reactor batch process vent... § 63.1407 Non-reactor batch process vent provisions. (a) Emission standards. (1) Owners or operators of non-reactor batch process vents located at new or existing affected sources with 0.25 tons per year...

  11. 40 CFR 205.57-7 - Acceptance and rejection of batch sequence.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 26 2012-07-01 2011-07-01 true Acceptance and rejection of batch....57-7 Acceptance and rejection of batch sequence. (a) The manufacturer will continue to inspect... rejection number appropriate for the cumulative number of batches inspected. The acceptance and...

  12. 40 CFR 205.57-7 - Acceptance and rejection of batch sequence.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 25 2014-07-01 2014-07-01 false Acceptance and rejection of batch....57-7 Acceptance and rejection of batch sequence. (a) The manufacturer will continue to inspect... rejection number appropriate for the cumulative number of batches inspected. The acceptance and...

  13. BatchPrimer3: A high throughput web application for PCR and sequencing primer design

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A new web primer design program, BatchPrimer3, is developed based on Primer3. BatchPrimer3 adopted the Primer3 core program as a major primer design engine to choose the best primer pairs. A new score-based primer picking module is incorporated into BatchPrimer3 and used to pick position-restricte...

  14. 40 CFR 63.1322 - Batch process vents-reference control technology.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 11 2010-07-01 2010-07-01 true Batch process vents-reference control technology. 63.1322 Section 63.1322 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Batch process vents—reference control technology. (a) Batch process vents. The owner or operator of...

  15. 40 CFR 63.487 - Batch front-end process vents-reference control technology.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 9 2010-07-01 2010-07-01 false Batch front-end process vents-reference control technology. 63.487 Section 63.487 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... § 63.487 Batch front-end process vents—reference control technology. (a) Batch front-end process...

  16. 21 CFR 111.123 - What quality control operations are required for the master manufacturing record, the batch...

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... the master manufacturing record, the batch production record, and manufacturing operations? 111.123... manufacturing record, the batch production record, and manufacturing operations? (a) Quality control operations for the master manufacturing record, the batch production record, and manufacturing operations...

  17. RADIOLYSIS OF ORGANIC COMPOUNDS IN THE ADSORBED STATE

    DOEpatents

    Sutherland, J.W.; Allen, A.O.

    1961-10-01

    >A method of forming branch chained hydrocarbons by means of energetic penetrating radiation is described. A solid zeolite substrate is admixed with a cobalt ion and is irradiated with a hydrocarbon adsorbed therein. Upon irradiation with gamma rays, there is an increased yield of branched and lower molecular straight chain compounds. (AEC)

  18. Ozonation of isoproturon adsorbed on silica particles under atmospheric conditions

    NASA Astrophysics Data System (ADS)

    Pflieger, Maryline; Grgić, Irena; Kitanovski, Zoran

    2012-12-01

    The results on heterogeneous ozonation of a phenylurea pesticide, isoproturon, under atmospheric conditions are presented for the first time in the present study. The study was carried out using an experimental device previously adopted and validated for the heterogeneous reactivity of organics toward ozone (Pflieger et al., 2011). Isoproturon was adsorbed on silica particles via a liquid-to-solid equilibrium with a load far below a monolayer (0.02% by weight/surface coverage of 0.5%). The rate constants were estimated by measuring the consumption of the organic (dark, T = 26 °C, RH < 1%). The experimental data were fitted by both the modified Langmuir-Hinshelwood and the Eley-Rideal patterns, resulting in atmospheric lifetimes of heterogeneous ozonation of 4 and 6 days, respectively (for 40 ppb of O3). Parameters, such as the number and the quantity of pesticides adsorbed on the solid support, which can significantly influence the heterogeneous kinetics, were investigated as well. The results obtained suggest that the organic compound is adsorbed in multilayer aggregates on the aerosol even though submonolayer coverage is assumed. The presence of a second herbicide, trifluralin, together with isoproturon on the aerosol surface does not affect the kinetics of ozonation, indicating that both compounds are adsorbed on different surface sites of silica particles.

  19. Chitosan membrane adsorber for low concentration copper ion removal.

    PubMed

    Wang, Xiaomin; Li, Yanxiang; Li, Haigang; Yang, Chuanfang

    2016-08-01

    Thin chitosan membranes with symmetric and interconnected pore structure were prepared using silica as porogen, and their physical properties including pore structure, pore size distribution, porosity and water affinity were analyzed. The membrane showed a maximum Cu(II) adsorption capacity of 87.5mg/g in static adsorption, and the adsorption fitted pseudo-second order kinetics and Toth adsorption isotherm. The membranes were then stacked in layers as an adsorber to remove small concentration Cu(II) from water dynamically. At feed concentration of 5mg/L, the adsorber could retain Cu(II) effectively when its thickness reached over 200μm, and the performance was further improved by using more membranes layers. Within a certain limit, the adsorber showed a 'flow-independent' loading behavior, an indication of fast mass transfer inside the membrane. The adsorption process was correlated well with bed depth service time (BDST) model, Thomas model and Yoon and Nelson model, and the adsorber was also found to be regenerable and re-usable. PMID:27112875

  20. Extracting uranium from seawater: Promising AI series adsorbents

    DOE PAGESBeta

    Das, Sadananda; Oyola, Y.; Mayes, Richard T.; Janke, Christopher James; Kuo, Li-Jung; Gill, Gary; Wood, Jordana; Dai, Sheng

    2015-11-10

    A series of adsorbent (AI10 through AI17) were successfully developed at ORNL by radiation induced graft polymerization (RIGP) of acrylonitrile (AN) and vinylphosphonic acid (VPA) (at different mole/mole ratios) onto high surface area polyethylene fiber, with higher degree of grafting which ranges from 110 300%. The grafted nitrile groups were converted to amidoxime groups by reaction with 10 wt% hydroxylamine at 80 C for 72 hours. The amidoximated adsorbents were then conditioned with 0.44M KOH at 80 C followed by screening at ORNL with simulated seawater spiked with 8 ppm uranium. Uranium adsorption capacity in simulated seawater screening ranged frommore » 171-187 g-U/kg-ads irrespective of %DOG. The performance of the adsorbents for uranium adsorption in natural seawater was also carried out using flow-through-column at Pacific Northwest National Laboratory (PNNL). The three hours KOH conditioning was better for higher uranium uptake than one hour. The adsorbent AI11 containing AN and VPA at the mole ration of 3.52, emerged as the potential candidate for higher uranium adsorption (3.35 g-U/Kg-ads.) after 56 days of exposure in the seawater in the flow-through-column. The rate vanadium adsorption over uranium was linearly increased throughout the 56 days exposure. The total vanadium uptake was ~5 times over uranium after 56 days.« less

  1. Extracting uranium from seawater: Promising AI series adsorbents

    SciTech Connect

    Das, Sadananda; Oyola, Y.; Mayes, Richard T.; Janke, Christopher James; Kuo, Li-Jung; Gill, Gary; Wood, Jordana; Dai, Sheng

    2015-11-10

    A series of adsorbent (AI10 through AI17) were successfully developed at ORNL by radiation induced graft polymerization (RIGP) of acrylonitrile (AN) and vinylphosphonic acid (VPA) (at different mole/mole ratios) onto high surface area polyethylene fiber, with higher degree of grafting which ranges from 110 300%. The grafted nitrile groups were converted to amidoxime groups by reaction with 10 wt% hydroxylamine at 80 C for 72 hours. The amidoximated adsorbents were then conditioned with 0.44M KOH at 80 C followed by screening at ORNL with simulated seawater spiked with 8 ppm uranium. Uranium adsorption capacity in simulated seawater screening ranged from 171-187 g-U/kg-ads irrespective of %DOG. The performance of the adsorbents for uranium adsorption in natural seawater was also carried out using flow-through-column at Pacific Northwest National Laboratory (PNNL). The three hours KOH conditioning was better for higher uranium uptake than one hour. The adsorbent AI11 containing AN and VPA at the mole ration of 3.52, emerged as the potential candidate for higher uranium adsorption (3.35 g-U/Kg-ads.) after 56 days of exposure in the seawater in the flow-through-column. The rate vanadium adsorption over uranium was linearly increased throughout the 56 days exposure. The total vanadium uptake was ~5 times over uranium after 56 days.

  2. Probing atomic positions of adsorbed ammonia molecules in zeolite.

    PubMed

    Ye, Lin; Lo, Benedict T W; Qu, Jin; Wilkinson, Ian; Hughes, Tim; Murray, Claire A; Tang, Chiu C; Tsang, Shik Chi Edman

    2016-02-25

    Atomic positions and interactions between adsorbed guest molecules, such as ammonia in H-ZSM-5 microporous solids, are for the first time revealed by making use of the change in the periodical scattering parameter using in situ synchrotron powder X-ray diffraction combined with refinement within experimental errors. PMID:26833032

  3. The density and refractive index of adsorbing protein layers.

    PubMed

    Vörös, Janos

    2004-07-01

    The structure of the adsorbing layers of native and denatured proteins (fibrinogen, gamma-immunoglobulin, albumin, and lysozyme) was studied on hydrophilic TiO(2) and hydrophobic Teflon-AF surfaces using the quartz crystal microbalance with dissipation and optical waveguide lightmode spectroscopy techniques. The density and the refractive index of the adsorbing protein layers could be determined from the complementary information provided by the two in situ instruments. The observed density and refractive index changes during the protein-adsorption process indicated the presence of conformational changes (e.g., partial unfolding) in general, especially upon contact with the hydrophobic surface. The structure of the formed layers was found to depend on the size of the proteins and on the experimental conditions. On the TiO(2) surface smaller proteins formed a denser layer than larger ones and the layer of unfolded proteins was less dense than that adsorbed from the native conformation. The hydrophobic surface induced denaturation and resulted in the formation of thin compact protein films of albumin and lysozyme. A linear correlation was found between the quartz crystal microbalance measured dissipation factor and the total water content of the layer, suggesting the existence of a dissipative process that is related to the solvent molecules present inside the adsorbed protein layer. Our measurements indicated that water and solvent molecules not only influence the 3D structure of proteins in solution but also play a crucial role in their adsorption onto surfaces. PMID:15240488

  4. Agricultural Waste as Sources for Mercury Adsorbents in Gas Applications

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Increased emphasis on reduction of mercury emissions from coal fired electric power plants have resulted in environmental regulations that may in the future require application of activated carbons as mercury sorbents. The sorbents could be injected into the flue gas stream where it adsorbs the mer...

  5. Agricultural By-products as Mercury Adsorbents in Gas Applications

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Increased emphasis on reduction of mercury emissions from coal fired electric power plans have resulted in environmental regulations that may in the future require application of activated carbons as mercury sorbents. The sorbents could be injected into the flue gas stream where is adsorbs the merc...

  6. Complexation of trace metals by adsorbed natural organic matter

    USGS Publications Warehouse

    Davis, J.A.

    1984-01-01

    The adsorption behavior and solution speciation of Cu(II) and Cd(II) were studied in model systems containing colloidal alumina particles and dissolved natural organic matter. At equilibrium a significant fraction of the alumina surface was covered by adsorbed organic matter. Cu(II) was partitioned primarily between the surface-bound organic matter and dissolved Cu-organic complexes in the aqueous phase. Complexation of Cu2+ with the functional groups of adsorbed organic matter was stronger than complexation with uncovered alumina surface hydroxyls. It is shown that the complexation of Cu(II) by adsorbed organic matter can be described by an apparent stability constant approximately equal to the value found for solution phase equilibria. In contrast, Cd(II) adsorption was not significantly affected by the presence of organic matter at the surface, due to weak complex formation with the organic ligands. The results demonstrate that general models of trace element partitioning in natural waters must consider the presence of adsorbed organic matter. ?? 1984.

  7. Gd uptake experiments for preliminary set of functionalized adsorbents

    SciTech Connect

    Clinton Noack

    2015-03-16

    These data summarize adsorption experiments conducted with Gd in 0.5 M NaCl. Results represent preliminary, proof-of-concept data utilizing fine-powder silica gel as the adsorbent support. Future testing will focus on larger, application-appropriate beads.

  8. DESIGNING FIXED-BED ADSORBERS TO REMOVE MIXTURES OF ORGANICS.

    EPA Science Inventory

    A liquid-phase granular activated carbon (GAC) pilot plant and a full-scale GAC adsorber were designed, built, and operated in order to evaluate their performance for treating a groundwater contaminated with several volatile and synthetic organic chemicals. Several empty bed con...

  9. Spectroscopic studies of pyrene adsorbed to titanium dioxide

    NASA Astrophysics Data System (ADS)

    Jin, Xing; Kusumoto, Yoshihumi

    2003-08-01

    Pyrene was adsorbed to a TiO 2 surface from water-alcohol mixture solutions at 25 °C and pyrene-TiO 2 particles were recovered by filtration. We found that the surface of TiO 2 thus recovered is relatively hydrophobic and pyrene is not decomposed but keep its fluorescence characteristics on the spectral measurement under ultraviolet excitation.

  10. Interactions of organic contaminants with mineral-adsorbed surfactants

    USGS Publications Warehouse

    Zhu, L.; Chen, B.; Tao, S.; Chiou, C.T.

    2003-01-01

    Sorption of organic contaminants (phenol, p-nitrophenol, and naphthalene) to natural solids (soils and bentonite) with and without myristylpyridinium bromide (MPB) cationic surfactant was studied to provide novel insight to interactions of contaminants with the mineral-adsorbed surfactant. Contaminant sorption coefficients with mineral-adsorbed surfactants, Kss, show a strong dependence on surfactant loading in the solid. At low surfactant levels, the Kss values increased with increasing sorbed surfactant mass, reached a maximum, and then decreased with increasing surfactant loading. The Kss values for contaminants were always higher than respective partition coefficients with surfactant micelles (Kmc) and natural organic matter (Koc). At examined MPB concentrations in water the three organic contaminants showed little solubility enhancement by MPB. At low sorbed-surfactant levels, the resulting mineral-adsorbed surfactant via the cation-exchange process appears to form a thin organic film, which effectively "adsorbs" the contaminants, resulting in very high Kss values. At high surfactant levels, the sorbed surfactant on minerals appears to form a bulklike medium that behaves essentially as a partition phase (rather than an adsorptive surface), with the resulting Kss being significantly decreased and less dependent on the MPB loading. The results provide a reference to the use of surfactants for remediation of contaminated soils/sediments or groundwater in engineered surfactant-enhanced washing.

  11. EVALUATING VARIOUS ADSORBENTS AND MEMBRANES FOR REMOVING RADIUM FROM GROUNDWATER

    EPA Science Inventory

    Field studies were conducted in Lemont, Ill., to evaluate specific adsorbents and reverse osmosis (RO) membranes for removing radium from groundwater. A radium-selective complexer and barium-sulfate-loaded alumina appeared to have the best potential for low-cost adsorption of ra...

  12. Hydraulic properties of adsorbed water films in unsaturated porous media

    SciTech Connect

    Tokunaga, Tetsu K.

    2009-03-01

    Adsorbed water films strongly influence residual water saturations and hydraulic conductivities in porous media at low saturations. Hydraulic properties of adsorbed water films in unsaturated porous media were investigated through combining Langmuir's film model with scaling analysis, without use of any adjustable parameters. Diffuse double layer influences are predicted to be important through the strong dependence of adsorbed water film thickness (f) on matric potential ({Psi}) and ion charge (z). Film thickness, film velocity, and unsaturated hydraulic conductivity are predicted to vary with z{sup -1}, z{sup -2}, and z{sup -3}, respectively. In monodisperse granular media, the characteristic grain size ({lambda}) controls film hydraulics through {lambda}{sup -1} scaling of (1) the perimeter length per unit cross sectional area over which films occur, (2) the critical matric potential ({Psi}{sub c}) below which films control flow, and (3) the magnitude of the unsaturated hydraulic conductivity when {Psi} < {Psi}{sub c}. While it is recognized that finer textured sediments have higher unsaturated hydraulic conductivities than coarser sands at intermediate {Psi}, the {lambda}{sup -1} scaling of hydraulic conductivity predicted here extends this understanding to very low saturations where all pores are drained. Extremely low unsaturated hydraulic conductivities are predicted under adsorbed film-controlled conditions (generally < 0.1 mm y{sup -1}). On flat surfaces, the film hydraulic diffusivity is shown to be constant (invariant with respect to {Psi}).

  13. Pulling adsorbed self-avoiding walks from a surface

    NASA Astrophysics Data System (ADS)

    Guttmann, Anthony J.; Jensen, I.; Whittington, S. G.

    2014-01-01

    We consider a self-avoiding walk model of polymer adsorption where the adsorbed polymer can be desorbed by the application of a force, concentrating on the case of the square lattice. Using series analysis methods we investigate the behaviour of the free energy of the system when there is an attractive potential ɛ with the surface and a force f applied at the last vertex, normal to the surface, and extract the phase boundary between the ballistic and adsorbed phases. We believe this to be exact to graphical accuracy. We give precise estimates of the location of the transition from the free phase to the ballistic phase, which we find to be at yc = exp (f/kBTc) = 1, and from the free phase to the adsorbed phase, which we estimate to be at ac = exp ( - ɛ/kBTc) = 1.775 615 ± 0.000 005. In addition we prove that the phase transition from the ballistic to the adsorbed phase is first order.

  14. Photochemistry of adsorbed nitrate on aluminum oxide particle surfaces.

    PubMed

    Rubasinghege, Gayan; Grassian, Vicki H

    2009-07-01

    Nitrogen oxides, including nitrogen dioxide and nitric acid, react with mineral dust particles in the atmosphere to yield adsorbed nitrate. Although nitrate ion is a well-known chromophore in natural waters, little is known about the surface photochemistry of nitrate adsorbed on mineral particles. In this study, nitrate adsorbed on aluminum oxide, a model system for mineral dust aerosol, is irradiated with broadband light (lambda > 300 nm) as a function of relative humidity (RH) in the presence of molecular oxygen. Upon irradiation, the nitrate ion readily undergoes photolysis to yield nitrogen-containing gas-phase products including NO(2), NO, and N(2)O, with NO being the major product. The relative ratio and product yields of these gas-phase products change with RH, with N(2)O production being highest at the higher relative humidities. Furthermore, an efficient dark reaction readily converts the major NO product into NO(2) during post-irradiation. Photochemical processes on mineral dust aerosol surfaces have the potential to impact the chemical balance of the atmosphere, yet little is known about these processes. In this study, the impact that adsorbed nitrate photochemistry may have on the renoxification of the atmosphere is discussed. PMID:19534452

  15. Batch Preheat for glass and related furnace processing operations

    SciTech Connect

    Energy & Environmental Resources, Inc

    2002-08-12

    The objectives that our development work addressed are: (1) Establish through lab tests a salt eutectic with a melting point of about 250 F and a working range of 250 to 1800 F. (2) Establish the most economical material of construction for the screened salt eutectics identified in the first objective. (3) Establish the material of construction for the salt heater liner. Objectives 2 and 3 were determined through corrosion tests using selected metallurgical samples. Successful completion of the above-stated goals will be incorporated in a heat recovery design that can be used in high temperature processes and furnaces, typical of which is the glass melting process. The process design incorporates the following unit operations: a vertical batch heater (whereby the batch flows down through tubes in a shell and tube exchanger; a molten salt eutectic is circulated on the shell side); a molten salt heater utilizing furnace flue gas in a radiation type heater (molten salt is circulated in the annular space between the inner and outer shells of the vertical heater, and flue gas passes from the furnace exhaust through the inner shell of the heater); a cantilever type molten salt circulating pump; and a jacketed mixer/conveyor to drive off moisture from the batch prior to feeding the batch to the vertical batch heater. Historically, radiation heaters, when applied to glass or fiberglass furnace recuperation, have experienced failures due to uneven heat flux rates, which increases internal stresses and spot overheating conditions. Low heat transfer coefficients result in requirements for large heat transfer surface areas in gas to gas or gas to air exchangers. Fouling is another factor that results in lower unit availability and reduced performance. These factors are accommodated in this process by the incorporation of several design features. The salt heater will be a vertical double wall radiation design, similar to radiation air heaters used in high temperature heat

  16. Nanopore reactive adsorbents for the high-efficiency removal of waste species

    DOEpatents

    Yang, Arthur Jing-Min; Zhang, Yuehua

    2005-01-04

    A nanoporous reactive adsorbent incorporates a relatively small number of relatively larger reactant, e.g., metal, enzyme, etc., particles (10) forming a discontinuous or continuous phase interspersed among and surrounded by a continuous phase of smaller adsorbent particles (12) and connected interstitial pores (14) therebetween. The reactive adsorbent can effectively remove inorganic or organic impurities in a liquid by causing the liquid to flow through the adsorbent. For example, silver ions may be adsorbed by the adsorbent particles (12) and reduced to metallic silver by reducing metal, such as ions, as the reactant particles (10). The column can be regenerated by backwashing with the liquid effluent containing, for example, acetic acid.

  17. Effect of adsorbent addition on floc formation and clarification.

    PubMed

    Younker, Jessica M; Walsh, Margaret E

    2016-07-01

    Adding adsorbent into the coagulation process is an emerging treatment solution for targeting hard-to-remove dissolved organic compounds from both drinking water and industrial wastewater. The impact of adding powdered activated carbon (PAC) or organoclay (OC) adsorbents with ferric chloride (FeCl3) coagulant was investigated in terms of potential changes to the coagulated flocs formed with respect to size, structure, and breakage and regrowth properties. The ability of dissolved air flotation (DAF) and sedimentation (SED) clarification processes to remove hybrid adsorbent-coagulant flocs was also evaluated through clarified water quality analysis of samples collected in bench-scale jar test experiments. The jar tests were conducted using both a synthetic fresh water and oily wastewater test water spiked with dissolved aromatic compounds phenol and naphthalene. Results of the study demonstrated that addition of adsorbent reduced the median coagulated floc size by up to 50% but did not affect floc strength or regrowth potential after application of high shear. Experimental results in fresh water demonstrated that sedimentation was more effective than DAF for clarification of both FeCl3-PAC and FeCl3-OC floc aggregates. However, experimental tests performed on the synthetic oily wastewater showed that coagulant-adsorbent floc aggregates were effectively removed with both DAF and sedimentation treatment, with lower residual turbidity achieved in clarified water samples than with coagulation treatment alone. Addition of OC or PAC into the coagulation process resulted in removals of over half, or nearly all of the dissolved aromatics, respectively. PMID:27064206

  18. Increased production of cellulases and xylanases by Penicillium echinulatum S1M29 in batch and fed-batch culture.

    PubMed

    dos Reis, Laísa; Fontana, Roselei Claudete; Delabona, Priscila da Silva; da Silva Lima, Deise Juliana; Camassola, Marli; Pradella, José Geraldo da Cruz; Dillon, Aldo José Pinheiro

    2013-10-01

    The development of more productive strains of microorganisms and processes that increase enzyme levels can contribute to the economically efficient production of second generation ethanol. To this end, cellulases and xylanases were produced with the S1M29 mutant strain of Penicillium echinulatum, using different concentrations of cellulose (20, 40, and 60 g L(-1)) in batch and fed-batch processes. The highest activities of FPase (8.3 U mL(-1)), endoglucanases (37.3 U mL(-1)), and xylanases (177 U mL(-1)) were obtained in fed-batch cultivation with 40 g L(-1) of cellulose. The P. echinulatum enzymatic broth and the commercial enzyme Cellic CTec2 were tested for hydrolysis of pretreated sugar cane bagasse. Maximum concentrations of glucose and xylose were achieved after 72 h of hydrolysis. Glucose yields of 28.0% and 27.0% were obtained using the P. echinulatum enzymatic extract and Cellic CTec2, respectively. PMID:23973981

  19. Kinetic studies on batch cultivation of Trichoderma reesei and application to enhance cellulase production by fed-batch fermentation.

    PubMed

    Ma, Lijuan; Li, Chen; Yang, Zhenhua; Jia, Wendi; Zhang, Dongyuan; Chen, Shulin

    2013-07-20

    Reducing the production cost of cellulase as the key enzyme for cellulose hydrolysis to fermentable sugars remains a major challenge for biofuel production. Because of the complexity of cellulase production, kinetic modeling and mass balance calculation can be used as effective tools for process design and optimization. In this study, kinetic models for cell growth, substrate consumption and cellulase production in batch fermentation were developed, and then applied in fed-batch fermentation to enhance cellulase production. Inhibition effect of substrate was considered and a modified Luedeking-Piret model was developed for cellulase production and substrate consumption according to the growth characteristics of Trichoderma reesei. The model predictions fit well with the experimental data. Simulation results showed that higher initial substrate concentration led to decrease of cellulase production rate. Mass balance and kinetic simulation results were applied to determine the feeding strategy. Cellulase production and its corresponding productivity increased by 82.13% after employing the proper feeding strategy in fed-batch fermentation. This method combining mathematics and chemometrics by kinetic modeling and mass balance can not only improve cellulase fermentation process, but also help to better understand the cellulase fermentation process. The model development can also provide insight to other similar fermentation processes. PMID:23702163

  20. Process development for the batch and bulk removal and recovery of a hazardous, water-soluble azo dye (Metanil Yellow) by adsorption over waste materials (Bottom Ash and De-Oiled Soya).

    PubMed

    Mittal, Alok; Gupta, V K; Malviya, Arti; Mittal, Jyoti

    2008-03-01

    Bottom Ash and De-Oiled Soya have been used as adsorbents for the removal of a hazardous azo dye-Metanil Yellow from its aqueous solutions. Adsorption of Metanil Yellow on these adsorbents has been studied as function of time, temperature, concentration and pH. Batch adsorption studies, kinetic studies and column operations enabled extraction of lethal dye from wastewaters. Adsorption equilibrium data confirms both Langmuir and Freundlich isotherm models and monolayer coverage of dye over adsorbents. Kinetic data have been employed to calculate specific rate constants, indicating thereby involvement of first order kinetics in the on-going adsorption and activation energy was determined as 0.813 and 1.060 kJ mol(-1) for Bottom Ash and De-Oiled Soya, respectively. For both adsorbents, the adsorption process has been found governing by film diffusion, over the entire concentration range. Column operations have also been performed for the bulk removal of the dye and also to examine the practical utilization of fixed bed adsorption technique in elimination of dangerous effluent. Saturation factors for Bottom Ash and De-Oiled Soya columns have been calculated as 99.15 and 99.38%, respectively. Attempts have also been made to regenerate the dye from the exhausted columns using aqueous sodium hydroxide as eluent. PMID:17659833

  1. Influence of exchange group of modified glycidyl methacrylate polymer on phenol removal: A study by batch and continuous flow processes.

    PubMed

    Aversa, Thiago Muza; da Silva, Carla Michele Frota; da Rocha, Paulo Cristiano Silva; Lucas, Elizabete Fernandes

    2016-11-01

    Contamination of water by phenol is potentially a serious problem due to its high toxicity and its acid character. In this way some treatment process to remove or reduce the phenol concentration before contaminated water disposal on the environment is required. Currently, phenol can be removed by charcoal adsorption, but this process does not allow easy regeneration of the adsorbent. In contrast, polymeric resins are easily regenerated and can be reused in others cycles of adsorption process. In this work, the interaction of phenol with two polymeric resins was investigated, one of them containing a weakly basic anionic exchange group (GD-DEA) and the other, a strongly basic group (GD-QUAT). Both ion exchange resins were obtained through chemical modifications from a base porous resin composed of glycidyl methacrylate (GMA) and divinyl benzene (DVB). Evaluation tests with resins were carried out with 30 mg/L of phenol in water solution, at pH 6 and 10, employing two distinct processes: (i) batch, to evaluate the effect of temperature, and (ii) continuous flow, to assess the breakthrough of the resins. Batch tests revealed that the systems did not follow the model proposed by Langmuir due to the negative values obtained for the constant b and for the maximum adsorption capacity, Q0. However, satisfactory results for the constants KF and n allowed assuming that the behavior of systems followed the Freundlich model, leading to the conclusion that resin GD-DEA had the best interaction with the phenol when in a solution having pH 10 (phenoxide ions). The continuous flow tests corroborated this conclusion since the performance of GD-DEA in removing phenol was also best at pH 10, indicating that the greater availability of the electron pair in the resin with the weakly basic donor group contributed to enhance the resin's interaction with the phenoxide ions. PMID:27494606

  2. Hollow-fiber-based adsorbers for gas separation by pressure-swing adsorption

    SciTech Connect

    Feng, X.; Pan, C.Y.; McMinis, C.W.; Ivory, J.; Ghosh, D.

    1998-07-01

    Hollow-fiber-based adsorbers for gas separation by pressure-swing adsorption (PSA) was studied experimentally. The high efficiency of hollow-fiber-based adsorbers for gas separation was illustrated by hydrogen separation using fine-powder-activated carbon and molecular sieve as adsorbents. The adsorption equilibrium and dynamics of the hollow-fiber adsorbers were determined. The pressure drop of the gas flowing through the adsorbers was also examined. The adsorbers were tested for hydrogen separation from nitrogen, carbon dioxide, and a multicomponent gas mixture simulating ammonia synthesis purge gas. The PSA systems using the hollow-fiber adsorbers were very effective for hydrogen purification. The high separation efficiency is derived from the fast mass-transfer rate and low pressure drop, two key features of hollow-fiber-based adsorbers.

  3. Removal of acutely hazardous pharmaceuticals from water using multi-template imprinted polymer adsorbent.

    PubMed

    Venkatesh, Avinash; Chopra, Nikita; Krupadam, Reddithota J

    2014-05-01

    Molecularly imprinted polymer adsorbent has been prepared to remove a group of recalcitrant and acutely hazardous (p-type) chemicals from water and wastewaters. The polymer adsorbent exhibited twofold higher adsorption capacity than the commercially used polystyrene divinylbenzene resin (XAD) and powdered activated carbon adsorbents. Higher adsorption capacity of the polymer adsorbent was explained on the basis of high specific surface area formed during molecular imprinting process. Freundlich isotherms drawn showed that the adsorption of p-type chemicals onto polymer adsorbent was kinetically faster than the other reference adsorbents. Matrix effect on adsorption of p-type chemicals was minimal, and also polymer adsorbent was amenable to regeneration by washing with water/methanol (3:1, v/v) solution. The polymer adsorbent was unaltered in its adsorption capacity up to 10 cycles of adsorption and desorption, which will be more desirable in cost reduction of treatment compared with single-time-use activated carbon. PMID:24499987

  4. Detecting the mass and position of an adsorbate on a drum resonator

    PubMed Central

    Zhang, Y.; Zhao, Y. P.

    2014-01-01

    The resonant frequency shifts of a circular membrane caused by an adsorbate are the sensing mechanism for a drum resonator. The adsorbate mass and position are the two major (unknown) parameters determining the resonant frequency shifts. There are infinite combinations of mass and position which can cause the same shift of one resonant frequency. Finding the mass and position of an adsorbate from the experimentally measured resonant frequencies forms an inverse problem. This study presents a straightforward method to determine the adsorbate mass and position by using the changes of two resonant frequencies. Because detecting the position of an adsorbate can be extremely difficult, especially when the adsorbate is as small as an atom or a molecule, this new inverse problem-solving method should be of some help to the mass resonator sensor application of detecting a single adsorbate. How to apply this method to the case of multiple adsorbates is also discussed. PMID:25294971

  5. Enhanced removal of Cr(VI) from aqueous solutions using polypyrrole wrapped oxidized MWCNTs nanocomposites adsorbent.

    PubMed

    Bhaumik, Madhumita; Agarwal, Shilpi; Gupta, Vinod Kumar; Maity, Arjun

    2016-05-15

    Polypyrrole wrapped oxidized multiwalled carbon nanotubes nanocomposites (PPy/OMWCNTs NCs) were prepared via in situ chemical polymerization of pyrrole (Py) monomer in the presence of OMWCNTs using FeCl3 as oxidant for the effective removal of hexavalent chromium [Cr(VI)]. The as-prepared PPy/OMWCNTs NCs were characterized by FE-SEM, HR-TEM, ATR-FTIR, XRD, XPS and BET method. Characterization results suggested that PPy was uniformly covered on the OMWCNTs surface and resulted in enhanced specific surface area. Adsorption experiments were carried out in batch sorption mode to investigate the effect of pH, dose of adsorbent, contact time, concentration of Cr(VI) and temperature. The adsorption of Cr(VI) on the nanocomposite surface was highly pH dependent and the kinetics of the adsorption followed the pseudo-second-order model. The adsorption isotherm data were in good conformity with the Langmuir isothermal model. The maximum adsorption capacity of the PPy/OMWCNTs NCs for Cr(VI) was 294mg/g at 25°C. The calculated values of the thermodynamic parameters such as ΔG(0) (-0.237kJ/mol), ΔH(0) (13.237kJ/mol) and ΔS(0) (0.0452kJ/mol/K) revealed that the adsorption process is spontaneous, endothermic and marked with an increase in randomness at the solid-liquid interface. The presence of co-existing ions slightly affected the Cr(VI) removal efficiency of the PPy/OMWCNTs. PMID:26962976

  6. Adsorption of Sulfamethazine from Environmentally Relevant Aqueous Matrices onto Hypercrosslinked Adsorbent MN250.

    PubMed

    Grimmett, Maria E

    2015-07-01

    Four hundred tons of sulfamethazine are fed to livestock annually in North America for disease prevention and growth promotion, but the majority is excreted unmetabolized into the environment. Due to its slow degradation and high mobility, sulfamethazine contaminates groundwater and causes aquatic ecosystem damage. Sulfamethazine remediation methods are not universally effective, necessitating newer techniques. Hypercrosslinked polystyrene adsorbents show promise because of high surface areas, durability, and regenerable properties. Using batch techniques, sulfamethazine adsorption onto Purolite MN250 was evaluated in the presence of dissolved humic acid and under variable pH and ionic strength. The adsorption capacity () of MN250 for sulfamethazine with humic acid was 109.3 mg g. In simulated groundwater, at pH 5 was 51 to 62% higher than at pH 9. The maximum at pH 7 (144.0 mg g) exceeded pH 5 performance (128.3 mg g). In 0.005 M KCl, was 181.0 mg g, which decreased by 34% in 0.05 M KCl. In 0.5 M, KCl, (153.4 mg g) increased 26% over 0.05 M KCl. For all matrices, equilibration was attained between 120 and 168 h, best fit by Ho's pseudo-second-order model. Overall, is pH dependent because the sulfamethazine speciation and the zeta potential of MN250 vary as a function of pH. Increasing ionic strength initially decreases by altering the activity coefficient of sulfamethazine and by altering the properties of the electrical double layer, while salting-out becomes prominent at seawater concentration. MN250's high sulfamethazine capacity in environmentally relevant aqueous matrices highlights its potential for groundwater remediation. PMID:26437099

  7. Persistence of Escherichia coli in batch and continuous vermicomposting systems.

    PubMed

    Hénault-Ethier, Louise; Martin, Vincent J J; Gélinas, Yves

    2016-10-01

    Vermicomposting is a biooxidation process in which epigeicearthworms act in synergy with microbial populations to degrade organic matter. Vermicomposting does not go through a thermophilic stage as required by North American legislations for pathogen eradication. We examined the survival of a Green Fluorescent Protein (GFP) labeled Escherichia coli MG1655 as a model for the survival of pathogenic bacteria in both small-scale batch and medium-scale continuously-operated systems to discern the influence of the earthworm Eisenia fetida, nutrient content and the indigenous vermicompost microbial community on pathogen abundance. In batch systems, the microbial community had the greatest influence on the rapid decline of E. coli populations, and the effect of earthworms was only visible in microbially-impoverishedvermicomposts. No significant earthworm density-dependent relationship was observed on E. coli survival under continuous operation. E. coli numbers decreased below the US EPA compost sanitation guidelines of 10(3)Colony Forming Units (CFU)/g (dry weight) within 18-21days for both the small-scale batch and medium-scale continuous systems, but it took up to 51days without earthworms and with an impoverished microbial community to reach the legal limit. Nutrient replenishment (i.e. organic carbon) provided by continuous feed input did not appear to extend E. coli survival. In fact, longer survival of E. coli was noticed in treatments where less total and labile sugars were available, suggesting that sugars may support potentially antagonist bacteria in the vermicompost. Total N, pH and humidity did not appear to affect E. coli survival. Several opportunistic human pathogens may be found in vermicompost, and their populations are likely kept in check by antagonists. PMID:27499290

  8. [Kinetics model for batch culture of white rot fungus].

    PubMed

    Xiong, Xiao-ping; Wen, Xiang-hua; Xu, Kang-ning; Bian, Bing-hui

    2008-02-01

    In order to understand ligninolytic enzymes production process during culture of white rot fungus, accordingly to direct the design of fermentation process, a kinetics model was built for the batch culture of Phanerochaete chrysosporium. The parameters in the model were calibrated based on the experimental data from free and immobilized culture separately. The difference between each variable's values calculated based on kinetics model and experimental data is within 15%. Comparing parameters for the free and the immobilized culture, it is found that maximum biomass concentrations are both 1.78 g/L; growth rate ratio of immobilized culture (0.6683 d(-1)) is larger than that of free culture (0.5144 d(-1)); very little glucose is consumed for biomass growth in free culture while in immobilized culture much glucose is used and ammonium nitrogen is consumed at a greater rate. Ligninolytic enzymes production process is non-growth related; fungal pellets can produce MnP (231 U/L) in free culture with a production rate of 115.8 U x (g x d)(-1) before peak and 26.1 U x (g x d)(-1) after peak, thus fed-batch is a possible mode to improve MnP production and fermentation efficiency. MnP (410 U/L) and LiP (721 U/L) can be produced in immobilized culture, but MnP and LiP production rate decrease from 80.1 U x (g x d)(-1) and 248.9 U x (g x d)(-1) to 6.04 U x (g x d)(-1) and 0 U x (g x d)(-1), respectively, indicating a proper feed moment is before the enzymes peak during fed-batch culture. PMID:18613526

  9. 40 CFR Table 6 to Subpart U of... - Group 1 Batch Front-End Process Vents and Aggregate Batch Vent Streams-Monitoring, Recordkeeping...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 10 2012-07-01 2012-07-01 false Group 1 Batch Front-End Process Vents and Aggregate Batch Vent Streams-Monitoring, Recordkeeping, and Reporting Requirements 6 Table 6 to Subpart U of Part 63 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS...

  10. 40 CFR Table 6 to Subpart U of... - Group 1 Batch Front-End Process Vents and Aggregate Batch Vent Streams-Monitoring, Recordkeeping...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 10 2014-07-01 2014-07-01 false Group 1 Batch Front-End Process Vents and Aggregate Batch Vent Streams-Monitoring, Recordkeeping, and Reporting Requirements 6 Table 6 to Subpart U of Part 63 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS...

  11. 40 CFR Table 7 to Subpart Jjj of... - Group 1 Batch Process Vents and Aggregate Batch Vent Streams-Monitoring, Recordkeeping, and...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 11 2011-07-01 2011-07-01 false Group 1 Batch Process Vents and Aggregate Batch Vent Streams-Monitoring, Recordkeeping, and Reporting Requirements 7 Table 7 to Subpart JJJ of Part 63 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR...

  12. Economic comparison of continuous and batch sintering of silicon nitride

    SciTech Connect

    Wittner, D.E.; Conover, J.J.; Knapp, V.A. ); Miller, C.W. Jr. )

    1993-06-01

    It is generally agreed that Si[sub 3]N[sub 4]-based compositions can be produced with reliable properties that are suitable for some automotive components. The major barrier to extensive application of Si[sub 3]N[sub 4] components is cost. Continuous sintering has recently been investigated as a means for cost-effective sintering of selected Si[sub 3]N[sub 4] compositions. Factors related to the cost of sintering in both belt furnaces and batch furnaces of increasing capacity - to allow sintering of the large number of parts required by the automotive industry - have been considered.

  13. REAL WASTE TESTING OF SLUDGE BATCH 5 MELTER FEED RHEOLOGY

    SciTech Connect

    Reboul, S.; Stone, M.

    2010-03-17

    Clogging of the melter feed loop at the Defense Waste Processing Facility (DWPF) has reduced the throughput of Sludge Batch 5 (SB5) processing. After completing a data review, DWPF attributed the clogging to the rheological properties of the Slurry Mix Evaporator (SME) project. The yield stress of the SB5 melter feed material was expected to be high, based on the relatively high pH of the SME product and the rheological results of a previous Chemical Process Cell (CPC) demonstration performed at the Savannah River National Laboratory (SRNL).

  14. Bounded Parallel-Batch Scheduling on Unrelated Parallel Machines

    NASA Astrophysics Data System (ADS)

    Miao, Cuixia; Zhang, Yuzhong; Wang, Chengfei

    In this paper, we consider the bounded parallel-batch scheduling problem on unrelated parallel machines. Problems R m |B|F are NP-hard for any objective function F. For this reason, we discuss the special case with p ij = p i for i = 1, 2, ⋯ , m , j = 1, 2, ⋯ , n. We give optimal algorithms for the general scheduling to minimize total weighted completion time, makespan and the number of tardy jobs. And we design pseudo-polynomial time algorithms for the case with rejection penalty to minimize the makespan and the total weighted completion time plus the total penalty of the rejected jobs, respectively.

  15. Determining gold in water by anion-exchange batch extraction

    USGS Publications Warehouse

    McHugh, J.B.

    1986-01-01

    This paper describes a batch procedure for determining gold in natural waters. It is completely adaptable to field operations. The water samples are filtered and acidified before they are equilibrated with an anion-exchange resin by shaking. The gold is then eluted with acetone-nitric acid solution, and the eluate evaporated to dryness. The residue is taken up in hydrobromic acid-bromine solution and the gold is extracted with methyl isobutyl ketone. The extract is electrothermally atomized in an atomic-absorption spectrophotometer. The limit of determination is 1 ng 1. ?? 1986.

  16. Nanoalloy electrocatalysis: Simulating cyclic voltammetry from configurational thermodynamics with adsorbates

    SciTech Connect

    Wang, Lin -Lin; Tan, Teck L.; Johnson, Duane D.

    2015-02-27

    We simulate the adsorption isotherms for alloyed nanoparticles (nanoalloys) with adsorbates to determine cyclic voltammetry (CV) during electrocatalysis. The effect of alloying on nanoparticle adsorption isotherms is provided by a hybrid-ensemble Monte Carlo simulation that uses the cluster expansion method extended to non-exchangeable coupled lattices for nanoalloys with adsorbates. Exemplified here for the hydrogen evolution reaction, a 2-dimensional CV is mapped for Pd–Pt nanoalloys as a function of both electrochemical potential and the global Pt composition, and shows a highly non-linear alloying effect on CV. Detailed features in CV arise from the interplay among the H-adsorption in multiple sites that is closely correlated with alloy configurations, which are in turn affected by the H-coverage. The origins of specific features in CV curves are assigned. As a result, the method provides a more complete means to design nanoalloys for electrocatalysis.

  17. Nanoalloy electrocatalysis: Simulating cyclic voltammetry from configurational thermodynamics with adsorbates

    DOE PAGESBeta

    Wang, Lin -Lin; Tan, Teck L.; Johnson, Duane D.

    2015-02-27

    We simulate the adsorption isotherms for alloyed nanoparticles (nanoalloys) with adsorbates to determine cyclic voltammetry (CV) during electrocatalysis. The effect of alloying on nanoparticle adsorption isotherms is provided by a hybrid-ensemble Monte Carlo simulation that uses the cluster expansion method extended to non-exchangeable coupled lattices for nanoalloys with adsorbates. Exemplified here for the hydrogen evolution reaction, a 2-dimensional CV is mapped for Pd–Pt nanoalloys as a function of both electrochemical potential and the global Pt composition, and shows a highly non-linear alloying effect on CV. Detailed features in CV arise from the interplay among the H-adsorption in multiple sites thatmore » is closely correlated with alloy configurations, which are in turn affected by the H-coverage. The origins of specific features in CV curves are assigned. As a result, the method provides a more complete means to design nanoalloys for electrocatalysis.« less

  18. Reflectivity studies on adsorbed block copolymers under shear

    SciTech Connect

    Smith, G.S.; Wages, S.; Baker, S.M.; Toprakcioglu, C.; Hadziioannou, G.

    1994-12-01

    The authors report neutron reflectivity data on (poly)styrene-(poly)ethylene oxide (PS-PEO) diblock copolymers adsorbed onto quartz from the selective solvent cyclohexane (a non-solvent for PEO and a poor solvent for PS). The PEO ``anchor block`` adsorbs strongly to form a thin layer on the quartz substrate, while the deuterated PS chains dangle into the solvent. They find that under static conditions the density profile of the PS block in a poor solvent can be well described by a Schultz function which is indicative of a polymer ``mushroom.`` Furthermore, they have studied the same system under shear at shear rates from 0--400s{sup {minus}1}. They find that there is a dramatic increase in the thickness of the PS layer under shear in cyclohexane and that the relaxation time from the shear-on profile back to the static profile is on the order of several days.

  19. Adsorbed molecules in external fields: Effect of confining potential.

    PubMed

    Tyagi, Ashish; Silotia, Poonam; Maan, Anjali; Prasad, Vinod

    2016-12-01

    We study the rotational excitation of a molecule adsorbed on a surface. As is well known the interaction potential between the surface and the molecule can be modeled in number of ways, depending on the molecular structure and the geometry under which the molecule is being adsorbed by the surface. We explore the effect of change of confining potential on the excitation, which is largely controlled by the static electric fields and continuous wave laser fields. We focus on dipolar molecules and hence we restrict ourselves to the first order interaction in field-molecule interaction potential either through permanent dipole moment or/and the molecular polarizability parameter. It is shown that confining potential shapes, strength of the confinement, strongly affect the excitation. We compare our results for different confining potentials. PMID:27387127

  20. Adsorbate-induced curvature and stiffening of graphene.

    PubMed

    Svatek, Simon A; Scott, Oliver R; Rivett, Jasmine P H; Wright, Katherine; Baldoni, Matteo; Bichoutskaia, Elena; Taniguchi, Takashi; Watanabe, Kenji; Marsden, Alexander J; Wilson, Neil R; Beton, Peter H

    2015-01-14

    The adsorption of the alkane tetratetracontane (TTC, C44H90) on graphene induces the formation of a curved surface stabilized by a gain in adsorption energy. This effect arises from a curvature-dependent variation of a moiré pattern due to the mismatch of the carbon-carbon separation in the adsorbed molecule and the period of graphene. The effect is observed when graphene is transferred onto a deformable substrate, which in our case is the interface between water layers adsorbed on mica and an organic solvent, but is not observed on more rigid substrates such as boron nitride. Our results show that molecular adsorption can be influenced by substrate curvature, provide an example of two-dimensional molecular self-assembly on a soft, responsive interface, and demonstrate that the mechanical properties of graphene may be modified by molecular adsorption, which is of relevance to nanomechanical systems, electronics, and membrane technology. PMID:25469625

  1. Hydrogen adsorption of ruthenium: Isosteres of solubility of adsorbed hydrogen

    SciTech Connect

    Zaginaichenko, S.Y.; Matysina, Z.A.; Schur, D.V.; Pishuk, V.K.

    1998-12-31

    The theoretical investigation of solubility isosteres of adsorbed hydrogen has been performed for free face (0001) of crystals with hexagonal close-packed lattice A3 of Mg type. The face free energy has been calculated and its dependence on temperature, pressure, hydrogen concentration and character of hydrogen atoms distribution over surface interstitial sites of different type has been defined. The equations of thermodynamic equilibrium and solubility of adsorbed hydrogen have been defined. The plots of isosteres in the region of phase transition from isotropic to anisotropic state have been constructed and it has been established that in anisotropic state the order in distribution of hydrogen atoms over interstitial sites of different type must become apparent. Comparison of the theoretical isosteres with experimental for ruthenium has been carried out, the isotropic-anisotropic state transition can stipulate a stepwise and break-like change in isosteres.

  2. Radiolysis of alanine adsorbed in a clay mineral

    NASA Astrophysics Data System (ADS)

    Aguilar-Ovando, Ellen Y.; Negrón-Mendoza, Alicia

    2013-07-01

    Optical activity in molecules is a chemical characteristic of living beings. In this work, we examine the hypothesis of the influence of different mineral surfaces on the development of a specific chirality in organic molecules when subjected to conditions simulating the primitive Earth during the period of chemical evolution. By using X-ray diffraction techniques and HPLC/ELSD to analyze aqueous suspensions of amino acids adsorbed on minerals irradiated in different doses with a cobalt-60 gamma source, the experiments attempt to prove the hypothesis that some solid surfaces (like clays and meteorite rocks) may have a concentration capacity and protective role against external sources of ionizing radiation (specifically γ-ray) for some organic compounds (like some amino acids) adsorbed on them. Preliminary results show a slight difference in the adsorption and radiolysis of the D-and L-alanine.

  3. Monte Carlo lattice models for adsorbed polymer conformation

    NASA Technical Reports Server (NTRS)

    Good, B. S.

    1985-01-01

    The adhesion between a polymer film and a metal surface is of great technological interest. However, the prediction of adhesion and wear properties of polymer coated metals is quite difficult because a fundamental understanding of the polymer surface interaction does not yet exist. A computer model for the conformation of a polymer molecule adsorbed on a surface is discussed. The chain conformation is assumed to be described by a partially directed random walk on a three dimensional simple cubic lattice. An attractive surface potential is incorporated into the model through the use of a random walk step probability distribution that is anisotropic in the direction normal to the attractive surface. The effects of variations in potential characteristics are qualitatively included by varying both the degree of anisotropy of the step distribution and the range of the anisotropy. Polymer conformation is characterized by the average end to end distance, average radius of gyration, and average number of chain segments adsorbed on the surface.

  4. Photocurrent response of bacteriorhodopsin adsorbed on bimolecular lipid membranes.

    PubMed

    Seta, P; Ormos, P; d'Epenoux, B; Gavach, C

    1980-06-10

    The photo response of bacteriorhodopsin adsorbed on a bimolecular lipid membrane has been investigated using short-circuit current measurements. The results revealed a biphasic current vs. time curve for the photocurrent at pH values of approx. 7. This phenomenon could be modified by altering either the value of the external applied electrical field or the proton concentration differences. The observed effects of the external applied voltage, pH gradient and lipophilic proton carriers enabled us to conclude that the bacteriorhodopsin can be adsorbed in two different states, which give rise to a pumping effect and a flux of protons in opposite directions. A theoretical analysis of the photocycle in relation to the electrical field which acts on the proton uptake and release is proposed. The main effect of this field is to diminish the pumping rate due to the proton motive force resulting from the creation of space-charge in the vicinity of purple membrane fragments. PMID:7388016

  5. In vitro binding of zearalenone to different adsorbents.

    PubMed

    Bueno, Dante J; Di Marco, Liliana; Oliver, Guillermo; Bardón, Alicia

    2005-03-01

    Zearalenone (ZEA) is a potent estrogenic metabolite produced by some Fusarium species. No treatment has been successfully employed to get rid of the ZEA contained in foods. This study was conducted to evaluate the ability (adsorptive power) of five adsorbents--activated carbon, bentonite, talc, sandstone, and calcium sulfate--to trap ZEA in vitro. Activated carbon was the best adsorbent, binding 100% ZEA (pH 3 and 7.3) at 0.1, 0.25, 0.5, and 1% dose levels. Bentonite, talc,and calcium sulfate were less efficient than activated carbon but still could bind ZEA to some extent. On the other hand, sandstone was inactive in the experimental conditions employed. Our results indicate that activated carbon could be a good candidate for detoxification of ZEA present in foods. PMID:15771192

  6. Topological features of engineered arrays of adsorbates in honeycomb lattices

    NASA Astrophysics Data System (ADS)

    Gonzalez-Arraga, Luis A.; Lado, J. L.; Guinea, Francisco

    2016-09-01

    Hydrogen adatoms are one of the most the promising proposals for the functionalization of graphene. The adatoms induce narrow resonances near the Dirac energy, which lead to the formation of magnetic moments. Furthermore, they also create local lattice distortions which enhance the spin-orbit coupling. The combination of magnetism and spin-orbit coupling allows for a rich variety of phases, some of which have non-trivial topological features. We analyze the interplay between magnetism and spin-orbit coupling in ordered arrays of adsorbates on honeycomb lattice monolayers, and classify the different phases that may arise. We extend our model to consider arrays of adsorbates in graphene-like crystals with stronger intrinsic spin-orbit couplings. We also consider a regime away from half-filling in which the Fermi level is at the bottom of the conduction band, we find a Berry curvature distribution corresponding to a Valley-Hall effect.

  7. Candidate Source of Flux Noise in SQUIDs: Adsorbed Oxygen Molecules.

    PubMed

    Wang, Hui; Shi, Chuntai; Hu, Jun; Han, Sungho; Yu, Clare C; Wu, R Q

    2015-08-14

    A major obstacle to using superconducting quantum interference devices (SQUIDs) as qubits is flux noise. We propose that the heretofore mysterious spins producing flux noise could be O_{2} molecules adsorbed on the surface. Using density functional theory calculations, we find that an O_{2} molecule adsorbed on an α-alumina surface has a magnetic moment of ~1.8 μ_{B}. The spin is oriented perpendicular to the axis of the O-O bond, the barrier to spin rotations is about 10 mK. Monte Carlo simulations of ferromagnetically coupled, anisotropic XY spins on a square lattice find 1/f magnetization noise, consistent with flux noise in Al SQUIDs. PMID:26317742

  8. Surface Adsorbate Fluctuations and Noise in Nanoelectromechanical Systems

    PubMed Central

    Yang, Y. T.; Callegari, C.; Feng, X. L.; Roukes, M. L.

    2013-01-01

    Physisorption on solid surfaces is important in both fundamental studies and technology. Adsorbates can also be critical for the performance of miniature electromechanical resonators and sensors. Advances in resonant nanoelectromechanical systems (NEMS), particularly mass sensitivity attaining the single-molecule level, make it possible to probe surface physics in a new regime, where a small number of adatoms cause a detectable frequency shift in a high quality factor (Q) NEMS resonator, and adsorbate fluctuations result in resonance frequency noise. Here we report measurements and analysis of the kinetics and fluctuations of physisorbed xenon (Xe) atoms on a high-Q NEMS resonator vibrating at 190.5 MHz. The measured adsorption spectrum and frequency noise, combined with analytic modeling of surface diffusion and adsorption–desorption processes, suggest that diffusion dominates the observed excess noise. This study also reveals new power laws of frequency noise induced by diffusion, which could be important in other low-dimensional nanoscale systems. PMID:21388120

  9. Enhanced Photovoltaic Properties of Potassium-Adsorbed Titania Nanotubes

    SciTech Connect

    Richter, C.; Jaye, C; Fischer, D; Lewis, L; Willey, R; Menon, L

    2009-01-01

    It is demonstrated that vertically-aligned titania nanotube planar arrays fabricated by electrochemical anodization using standard potassium-containing electrolytes invariably contain a significant amount of surface-adsorbed potassium ions, hitherto undetected, that affect the titania photoelectrochemical or PEC performance. Synchrotron-based near edge X-ray absorption fine structure (NEXAFS) spectroscopy reveals the strong ionic nature of surface potassium-titania bonds that alters the PEC performance over that of pure titania nanotubes through reduction of the external electrical bias needed to produce hydrogen at maximum efficiency. This result implies that the external electrical energy input required per liter of solar hydrogen produced with potassium-adsorbed titania nanotubes may be reduced. Tailoring the potassium content may thus be an alternative means to fine-tune the photoelectrochemical response of TiO2 nanotube-based PEC electrodes.

  10. pyIAST: Ideal adsorbed solution theory (IAST) Python package

    NASA Astrophysics Data System (ADS)

    Simon, Cory M.; Smit, Berend; Haranczyk, Maciej

    2016-03-01

    Ideal adsorbed solution theory (IAST) is a widely-used thermodynamic framework to readily predict mixed-gas adsorption isotherms from a set of pure-component adsorption isotherms. We present an open-source, user-friendly Python package, pyIAST, to perform IAST calculations for an arbitrary number of components. pyIAST supports several common analytical models to characterize the pure-component isotherms from experimental or simulated data. Alternatively, pyIAST can use numerical quadrature to compute the spreading pressure for IAST calculations by interpolating the pure-component isotherm data. pyIAST can also perform reverse IAST calculations, where one seeks the required gas phase composition to yield a desired adsorbed phase composition.

  11. Forces and pressures in adsorbing partially directed walks

    NASA Astrophysics Data System (ADS)

    Janse van Rensburg, E. J.; Prellberg, T.

    2016-05-01

    Polymers in confined spaces lose conformational entropy. This induces a net repulsive entropic force on the walls of the confining space. A model for this phenomenon is a lattice walk between confining walls, and in this paper a model of an adsorbing partially directed walk is used. The walk is placed in a half square lattice {{{L}}}+2 with boundary \\partial {{{L}}}+2, and confined between two vertical parallel walls, which are vertical lines in the lattice, a distance w apart. The free energy of the walk is determined, as a function of w, for walks with endpoints in the confining walls and adsorbing in \\partial {{{L}}}+2. This gives the entropic force on the confining walls as a function of w. It is shown that there are zero force points in this model and the locations of these points are determined, in some cases exactly, and in other cases asymptotically.

  12. Allantoin as a solid phase adsorbent for removing endotoxins.

    PubMed

    Vagenende, Vincent; Ching, Tim-Jang; Chua, Rui-Jing; Gagnon, Pete

    2013-10-01

    In this study we present a simple and robust method for removing endotoxins from protein solutions by using crystals of the small-molecule compound 2,5-dioxo-4-imidazolidinyl urea (allantoin) as a solid phase adsorbent. Allantoin crystalline powder is added to a protein solution at supersaturated concentrations, endotoxins bind and undissolved allantoin crystals with bound endotoxins are removed by filtration or centrifugation. This method removes an average of 99.98% endotoxin for 20 test proteins. The average protein recovery is ∼80%. Endotoxin binding is largely independent of pH, conductivity, reducing agent and various organic solvents. This is consistent with a hydrogen-bond based binding mechanism. Allantoin does not affect protein activity and stability, and the use of allantoin as a solid phase adsorbent provides better endotoxin removal than anion exchange, polymixin affinity and biological affinity methods for endotoxin clearance. PMID:24001944

  13. Radiolysis of alanine adsorbed in a clay mineral

    SciTech Connect

    Aguilar-Ovando, Ellen Y.; Negron-Mendoza, Alicia

    2013-07-03

    Optical activity in molecules is a chemical characteristic of living beings. In this work, we examine the hypothesis of the influence of different mineral surfaces on the development of a specific chirality in organic molecules when subjected to conditions simulating the primitive Earth during the period of chemical evolution. By using X-ray diffraction techniques and HPLC/ELSD to analyze aqueous suspensions of amino acids adsorbed on minerals irradiated in different doses with a cobalt-60 gamma source, the experiments attempt to prove the hypothesis that some solid surfaces (like clays and meteorite rocks) may have a concentration capacity and protective role against external sources of ionizing radiation (specifically {gamma}-ray) for some organic compounds (like some amino acids) adsorbed on them. Preliminary results show a slight difference in the adsorption and radiolysis of the D-and L-alanine.

  14. Theory of optical excitation of adsorbed rare gas atoms

    NASA Astrophysics Data System (ADS)

    Tsukada, Masaru; Brenig, Wilhelm

    1985-03-01

    Optical absorption spectra of rare-gas atoms adsorbed on metal surfaces exhibit a bimodal behavior, which, according to Cunningham, Greenlaw and Flynn, can be correlated with the difference I' - φ (where I' is the ionization energy of the excited (gas phase) state of the rare gas atom and φ the work function of the metal) controlling the energetics of charge transfer from the excited atom to the metal. In this paper we propose a model which allows to treat this charge transfer and some accompanying many-body effects in detail. Strong Coulomb attraction between the core hole and the excited electron on the adatom is taken into account as well as the interaction with surface plasmons. An improved charge transfer criterion is obtained which, besides the important parameter I∗ - φ, involves additional parameters such as the adsorbate-metal coupling strength and the plasmon frequency.

  15. Candida albicans binds to saliva proteins selectively adsorbed to silicone.

    PubMed

    Holmes, Ann R; van der Wielen, Pauline; Cannon, Richard D; Ruske, Dean; Dawes, Patrick

    2006-10-01

    Explanted voice prostheses obtained from 5 patients at the time of prosthesis replacement were consistently colonized by yeast, in particular Candida albicans. A simple, reproducible, in vitro model of C. albicans adherence to saliva-coated voice prosthesis silicone was developed. Whole saliva promoted adherence of C. albicans to silicone in a dose-dependent manner. Saliva rinses from voice prosthesis patients also promoted binding of C. albicans to silicone in vitro (mean adherence 14.9% +/- 2.8% of input C. albicans cells). This was significantly higher than C. albicans adherence to silicone in the absence of saliva (P < .001) or adherence promoted by saliva rinses from healthy volunteers (P < .005). Polyacrylamide gel electrophoresis analysis and a blot overlay adherence assay revealed that certain salivary proteins were selectively adsorbed to silicone and that C. albicans yeast cells adhered specifically to the adsorbed salivary proteins. PMID:16997116

  16. Adsorbed self-avoiding walks subject to a force

    NASA Astrophysics Data System (ADS)

    Janse van Rensburg, E. J.; Whittington, S. G.

    2013-11-01

    We consider a self-avoiding walk model of polymer adsorption where the adsorbed polymer can be desorbed by the application of a force. In this paper the force is applied normal to the surface at the last vertex of the walk. We prove that the appropriate limiting free energy exists where there is an applied force and a surface potential term, and prove that this free energy is convex in appropriate variables. We then derive an expression for the limiting free energy in terms of the free energy without a force and the free energy with no surface interaction. Finally we show that there is a phase boundary between the adsorbed phase and the desorbed phase in the presence of a force, prove some qualitative properties of this boundary and derive bounds on the location of the boundary.

  17. An innovative zinc oxide-coated zeolite adsorbent for removal of humic acid

    EPA Science Inventory

    Zinc oxide (ZnO)-coated zeolite adsorbents were developed by both nitric acid modification and Zn(NO3)2•6H2O functionalization of zeolite. The developed adsorbents were used for the removal of humic acid (HA) from aqueous solutions. The adsorption capacity of the adsorbents at 21...

  18. Development of the Molecular Adsorber Coating for Spacecraft and Instrument Interiors

    NASA Technical Reports Server (NTRS)

    Abraham, Nithin

    2011-01-01

    On-orbit Molecular Contamination occurs when materials outgas and deposit onto very sensitive interior surfaces of the spacecraft and instruments. The current solution, Molecular Adsorber Pucks, has disadvantages, which are reviewed. A new innovative solution, Molecular Adsorber Coating (MAC), is currently being formulated, optimized, and tested. It is a sprayable alternative composed of Zeolite-based coating with adsorbing properties.

  19. An innovative zinc oxide-coated zeolite adsorbent for removal of humic acid

    EPA Science Inventory

    Zinc oxide (ZnO)-coated zeolite adsorbents were developed by both nitric acid modification and Zn(NO3)2•6H2O functionalization of zeolite. The developed adsorbents were used for the removal of humic acid (HA) from aqueous solutions. The adsorption capacity of the adsorbents ...

  20. Nuclear spin heat capacity of 3He adsorbed on graphite

    NASA Astrophysics Data System (ADS)

    Greywall, Dennis S.

    1989-10-01

    The heat capacity of 3He adsorbed on graphite has been measured for films between one and five atomic layers and for temperatures between 2 and 200 mK. These results are compared with recent magnetization data which also show several anomalies in this coverage regime. Prior to third layer promotion the second layer is found to solidify into a registered structure with unusual propertis. This contradicts the model proposed to explain the NMR measurements.